feat: add session memory replay consistency harness

tests/sessions/replay_cases/README.md

@@ -0,0 +1,31 @@
+# Replay Consistency Design
+
+The replay harness loads ten JSONL traces and applies each operation to a paired
+SessionService and MemoryService. InMemory and SQLite run by default, so CI gets
+a real persistence round trip without external infrastructure. Set
+`TRPC_REPLAY_BACKENDS=inmemory` for the smallest mode. A disposable SQL or Redis
+backend can be added with `TRPC_REPLAY_SQL_URL` or `TRPC_REPLAY_REDIS_URL`;
+explicit backend selection uses `TRPC_REPLAY_BACKENDS=inmemory,sql,redis`.
+
+Comparison removes only non-business variance. Physical event IDs map to logical
+replay IDs, wall-clock timestamps become a typed marker, JSON objects are
+compared structurally, and memory matches are sorted because equal-keyword
+ranking is not part of the MemoryService contract. Summary text uses Unicode
+NFKC, case folding, and whitespace collapse. Summary ownership, version,
+supersedes relation, event counts, and active anchor count remain exact. The
+report records any raw memory-order or recovery-mechanism difference under a
+narrow `allowed_diffs` rule; content, count, state, event order, and summary
+metadata are never globally ignored.
+
+Duplicate append and failed summary replacement cases use compensating replay
+recovery, then reload the backend to detect duplicate events, dirty state, stale
+anchors, or an incorrect cached summary. Per-backend expectations keep
+InMemory-only runs meaningful, while pairwise comparison exposes backend drift.
+Every unexpected difference includes the logical session ID, JSON field path,
+event index or summary ID when applicable, and both backend values. Run the
+harness directly to refresh the report:
+
+```bash
+python -m tests.sessions.replay_harness \
+  --output session_memory_summary_diff_report.json
+```

tests/sessions/replay_cases/session_memory_summary.jsonl

@@ -0,0 +1,10 @@
+{"case_id":"single_turn","description":"One user message followed by one assistant response.","session_id":"session-single","operations":[{"op":"append_event","event":{"id":"single-user-1","timestamp":1700000001.0,"author":"user","role":"user","text":"Hello, replay harness."}},{"op":"append_event","event":{"id":"single-agent-1","timestamp":1700000002.0,"author":"assistant","role":"model","text":"Hello. How can I help?"}}],"expect":{"active_event_count":2,"historical_event_count":0,"state":{},"summary_present":false}}
+{"case_id":"multi_turn","description":"Three complete user and assistant turns preserve event order.","session_id":"session-multi","operations":[{"op":"append_event","event":{"id":"multi-user-1","timestamp":1700000011.0,"author":"user","role":"user","text":"My name is Ada."}},{"op":"append_event","event":{"id":"multi-agent-1","timestamp":1700000012.0,"author":"assistant","role":"model","text":"Nice to meet you, Ada."}},{"op":"append_event","event":{"id":"multi-user-2","timestamp":1700000013.0,"author":"user","role":"user","text":"What is my name?"}},{"op":"append_event","event":{"id":"multi-agent-2","timestamp":1700000014.0,"author":"assistant","role":"model","text":"Your name is Ada."}},{"op":"append_event","event":{"id":"multi-user-3","timestamp":1700000015.0,"author":"user","role":"user","text":"Remember that."}},{"op":"append_event","event":{"id":"multi-agent-3","timestamp":1700000016.0,"author":"assistant","role":"model","text":"I will remember it."}}],"expect":{"active_event_count":6,"historical_event_count":0,"state":{},"summary_present":false}}
+{"case_id":"tool_call","description":"A function call and matching function response round trip through storage.","session_id":"session-tool","operations":[{"op":"append_event","event":{"id":"tool-user-1","timestamp":1700000021.0,"author":"user","role":"user","text":"What is the weather in Shenzhen?"}},{"op":"append_event","event":{"id":"tool-call-1","timestamp":1700000022.0,"author":"assistant","role":"model","function_call":{"id":"call-weather-1","name":"get_weather","args":{"city":"Shenzhen","unit":"celsius"}}}},{"op":"append_event","event":{"id":"tool-response-1","timestamp":1700000023.0,"author":"tool","role":"function","function_response":{"id":"call-weather-1","name":"get_weather","response":{"temperature":31,"condition":"sunny"}}}},{"op":"append_event","event":{"id":"tool-agent-1","timestamp":1700000024.0,"author":"assistant","role":"model","text":"It is 31 C and sunny in Shenzhen."}}],"expect":{"active_event_count":4,"historical_event_count":0,"state":{},"summary_present":false}}
+{"case_id":"state_overwrite","description":"Session, user, and app state updates use last-write-wins semantics.","session_id":"session-state","initial_state":{"theme":"light","user:locale":"en","app:policy":"v1"},"operations":[{"op":"state_update","event":{"id":"state-update-1","timestamp":1700000031.0,"author":"system","state_delta":{"theme":"dark","counter":1}}},{"op":"state_update","event":{"id":"state-update-2","timestamp":1700000032.0,"author":"system","state_delta":{"theme":"solarized","counter":2,"user:locale":"fr","app:policy":"v2","temp:request":"not-persisted"}}}],"expect":{"active_event_count":2,"historical_event_count":0,"state":{"theme":"solarized","counter":2,"user:locale":"fr","app:policy":"v2"},"summary_present":false}}
+{"case_id":"memory_write_read","description":"Preference and fact memories are stored and retrieved by keyword.","session_id":"session-memory","operations":[{"op":"append_event","event":{"id":"memory-user-1","timestamp":1700000041.0,"author":"user","role":"user","text":"I prefer green tea without sugar."}},{"op":"append_event","event":{"id":"memory-agent-1","timestamp":1700000042.0,"author":"assistant","role":"model","text":"I will remember your tea preference."}},{"op":"append_event","event":{"id":"memory-user-2","timestamp":1700000043.0,"author":"user","role":"user","text":"My timezone is Asia Shanghai."}},{"op":"append_event","event":{"id":"memory-agent-2","timestamp":1700000044.0,"author":"assistant","role":"model","text":"Your timezone preference is saved."}},{"op":"store_memory"},{"op":"search_memory","label":"tea_preference","query":"tea"},{"op":"search_memory","label":"timezone_fact","query":"timezone"}],"expect":{"active_event_count":4,"historical_event_count":0,"state":{},"memory_counts":{"tea_preference":2,"timezone_fact":2},"summary_present":false}}
+{"case_id":"summary_create_update","description":"A second summary supersedes the first revision without losing ownership metadata.","session_id":"session-summary-update","operations":[{"op":"append_event","event":{"id":"summary-u1","timestamp":1700000051.0,"author":"user","role":"user","text":"Plan a release checklist."}},{"op":"append_event","event":{"id":"summary-a1","timestamp":1700000052.0,"author":"assistant","role":"model","text":"Start with tests and changelog."}},{"op":"append_event","event":{"id":"summary-u2","timestamp":1700000053.0,"author":"user","role":"user","text":"Add a security review."}},{"op":"append_event","event":{"id":"summary-a2","timestamp":1700000054.0,"author":"assistant","role":"model","text":"Security review added."}},{"op":"append_event","event":{"id":"summary-u3","timestamp":1700000055.0,"author":"user","role":"user","text":"Keep the latest decisions."}},{"op":"append_event","event":{"id":"summary-a3","timestamp":1700000056.0,"author":"assistant","role":"model","text":"The decisions are retained."}},{"op":"summarize","summary_id":"summary-update-v1","version":1,"text":"The release checklist includes tests, changelog, and a security review."},{"op":"append_event","event":{"id":"summary-u4","timestamp":1700000057.0,"author":"user","role":"user","text":"The release owner is Lin."}},{"op":"append_event","event":{"id":"summary-a4","timestamp":1700000058.0,"author":"assistant","role":"model","text":"Lin is the release owner."}},{"op":"summarize","summary_id":"summary-update-v2","version":2,"supersedes":"summary-update-v1","text":"The release needs tests, changelog, and security review. Lin owns the release."}],"expect":{"active_event_count":3,"historical_event_count":7,"state":{},"summary_present":true,"summary_id":"summary-update-v2","summary_version":2,"summary_supersedes":"summary-update-v1","summary_text":"the release needs tests, changelog, and security review. lin owns the release.","summary_session_id":"session-summary-update","summary_anchor_count":1}}
+{"case_id":"summary_event_truncation","description":"A summary anchor, retained events, and later events reconstruct compressed context.","session_id":"session-summary-truncate","operations":[{"op":"append_event","event":{"id":"truncate-u1","timestamp":1700000061.0,"author":"user","role":"user","text":"The project codename is Orion."}},{"op":"append_event","event":{"id":"truncate-a1","timestamp":1700000062.0,"author":"assistant","role":"model","text":"Codename Orion noted."}},{"op":"append_event","event":{"id":"truncate-u2","timestamp":1700000063.0,"author":"user","role":"user","text":"The target date is Friday."}},{"op":"append_event","event":{"id":"truncate-a2","timestamp":1700000064.0,"author":"assistant","role":"model","text":"Friday is the target date."}},{"op":"append_event","event":{"id":"truncate-u3","timestamp":1700000065.0,"author":"user","role":"user","text":"Keep two recent events."}},{"op":"append_event","event":{"id":"truncate-a3","timestamp":1700000066.0,"author":"assistant","role":"model","text":"Two recent events will remain."}},{"op":"summarize","summary_id":"summary-truncate-v1","version":1,"text":"Project Orion targets Friday."},{"op":"append_event","event":{"id":"truncate-u4","timestamp":1700000067.0,"author":"user","role":"user","text":"Add a deployment rehearsal."}},{"op":"append_event","event":{"id":"truncate-a4","timestamp":1700000068.0,"author":"assistant","role":"model","text":"Deployment rehearsal added."}}],"expect":{"active_event_count":5,"historical_event_count":4,"state":{},"summary_present":true,"summary_id":"summary-truncate-v1","summary_version":1,"summary_text":"project orion targets friday.","summary_session_id":"session-summary-truncate","summary_anchor_count":1}}
+{"case_id":"summary_semantic_normalization","description":"Summary comparison normalizes Unicode case and whitespace but preserves metadata.","session_id":"session-summary-semantic","operations":[{"op":"append_event","event":{"id":"semantic-u1","timestamp":1700000071.0,"author":"user","role":"user","text":"I chose tea."}},{"op":"append_event","event":{"id":"semantic-a1","timestamp":1700000072.0,"author":"assistant","role":"model","text":"Tea choice recorded."}},{"op":"append_event","event":{"id":"semantic-u2","timestamp":1700000073.0,"author":"user","role":"user","text":"Brew it next."}},{"op":"append_event","event":{"id":"semantic-a2","timestamp":1700000074.0,"author":"assistant","role":"model","text":"Brewing is next."}},{"op":"summarize","summary_id":"summary-semantic-v1","version":1,"text":"  User   chose TEA.\nNext:   brew.  "}],"expect":{"active_event_count":3,"historical_event_count":2,"state":{},"summary_present":true,"summary_id":"summary-semantic-v1","summary_version":1,"summary_text":"user chose tea. next: brew.","summary_session_id":"session-summary-semantic","summary_anchor_count":1}}
+{"case_id":"duplicate_write_recovery","description":"A retried event write is detected and recovered to one logical event.","session_id":"session-duplicate","operations":[{"op":"append_event","event":{"id":"duplicate-u1","timestamp":1700000081.0,"author":"user","role":"user","text":"Run once."}},{"op":"append_event","event":{"id":"duplicate-a1","timestamp":1700000082.0,"author":"assistant","role":"model","text":"Completed once."}},{"op":"duplicate_append","event":{"id":"duplicate-a1","timestamp":1700000082.0,"author":"assistant","role":"model","text":"Completed once."}}],"expect":{"active_event_count":2,"historical_event_count":0,"state":{},"summary_present":false,"unique_event_ids":true,"recovery_kinds":["duplicate_append"]}}
+{"case_id":"failed_summary_recovery","description":"A failure after summary replacement restores events, state, and the prior summary revision.","session_id":"session-failed-summary","operations":[{"op":"append_event","event":{"id":"failure-u1","timestamp":1700000091.0,"author":"user","role":"user","text":"The migration starts Monday."}},{"op":"append_event","event":{"id":"failure-a1","timestamp":1700000092.0,"author":"assistant","role":"model","text":"Monday start recorded."}},{"op":"append_event","event":{"id":"failure-u2","timestamp":1700000093.0,"author":"user","role":"user","text":"Backups are mandatory."}},{"op":"append_event","event":{"id":"failure-a2","timestamp":1700000094.0,"author":"assistant","role":"model","text":"Backups are mandatory."}},{"op":"append_event","event":{"id":"failure-u3","timestamp":1700000095.0,"author":"user","role":"user","text":"Keep the newest turn."}},{"op":"append_event","event":{"id":"failure-a3","timestamp":1700000096.0,"author":"assistant","role":"model","text":"Newest turn retained."}},{"op":"summarize","summary_id":"summary-failure-v1","version":1,"text":"Migration starts Monday and requires backups."},{"op":"append_event","event":{"id":"failure-u4","timestamp":1700000097.0,"author":"user","role":"user","text":"Notify operations."}},{"op":"append_event","event":{"id":"failure-a4","timestamp":1700000098.0,"author":"assistant","role":"model","text":"Operations will be notified."}},{"op":"fail_summary","summary_id":"summary-failure-v2","version":2,"supersedes":"summary-failure-v1","text":"Migration starts Monday, requires backups, and operations must be notified."}],"expect":{"active_event_count":5,"historical_event_count":4,"state":{},"summary_present":true,"summary_id":"summary-failure-v1","summary_version":1,"summary_text":"migration starts monday and requires backups.","summary_session_id":"session-failed-summary","summary_anchor_count":1,"recovery_kinds":["summary_update"]}}