fix(stage-router): recognize Hermes compaction

[ryan-lempka]

Stage already keeps compacted conversations on the capable model, but it did not recognize Hermes' compaction headers. This change recognizes Hermes' summary and resumed-task headers and applies the existing compaction override. Verified with real Hermes compaction through Switchyard using a scripted model endpoint: requests after compaction now stay on the capable model, while earlier routing stays unchanged. All local tests and checks pass.

Summary by CodeRabbit

• Bug Fixes
  • Compaction summaries are now recognized for both Claude Code and Hermes, including when they appear within user or assistant messages. Existing Claude Code marker detection is preserved, while tool-result content does not trigger compaction detection.

[github-actions]

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[coderabbitai]

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ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 2bd647e and e361811.

📒 Files selected for processing (1)

• crates/libsy/src/algorithms/util/tool_signals.rs

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Walkthrough

Compaction detection now recognizes two Hermes summary headers in user and assistant text, in addition to the existing Claude Code marker. Tests cover matching cases and text that must not trigger detection.

Changes

Compaction Detection

Layer / File(s)	Summary
Hermes header detection and tests crates/libsy/src/algorithms/util/tool_signals.rs	The detector lowercases text and checks whether a trimmed line starts with either Hermes header. Tests cover user and assistant messages, existing text, tool-result exclusions, and non-matching text.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~8 minutes

Merge Risk: ⚪ Minimal · up to e3618

The pinned Hermes compaction summary matches the new detector, so the intended capable-model routing remains available. No actionable merge-blocking risk is established.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely identifies the main change: recognizing Hermes compaction in the stage router.
Docstring Coverage	✅ Passed	Docstring coverage is 80.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 5 functions across 1 files.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

• Autopilot · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts

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_{A rabbit checks each line with care,
Two Hermes headers meet the snare.
Claude's marker keeps its place,
Tool results pass without a trace.
The test burrow rests, all clear.}

_{Comment @coderabbitai help to get the list of available commands.}