fix(copilot): keep Copilot modular instructions split at user-scope since supported - reverts #1619

[kilianpaquier]

Description

Reverts changes introduced in #1619 since Copilot CLI (and VSCode Chat) support user-scope ~/.copilot/instructions/**/*.instructions.md.

Fixes #650.

Type of change

• Bug fix
• New feature
• Documentation
• Maintenance / refactor

Testing

• Tested locally
• All existing tests pass
• Added tests for new functionality (if applicable)

Spec conformance (OpenAPM v0.1)

If this PR changes behaviour that an OpenAPM v0.1 req-XXX covers,
confirm the three-step ritual (see CONTRIBUTING.md "Adding or
changing a normative requirement"):

• Spec edit: docs/src/content/docs/specs/openapm-v0.1.md updated
  (new/changed <a id="req-XXX"></a> anchor + prose + Appendix C
  row).
• Manifest edit: docs/src/content/docs/specs/manifests/openapm-v0.1.requirements.yml
  updated.
• Test edit: a @pytest.mark.req("req-XXX") test under
  tests/spec_conformance/ added or extended.
• CONFORMANCE.{md,json} regenerated via
  uv run --extra dev python -m tests.spec_conformance.gen_statement
  and committed.
• N/A -- this PR does not change OpenAPM-observable behaviour.

Proof of tests

Current APM installed version v0.24.1

❯ apm --version
Agent Package Manager (APM) CLI version 0.24.1 (4257698)

❯ apm install kilianpaquier/agent-rules -g --target claude,copilot
[i] Installing to user scope (~/.apm/)
[!] User-scope primitives are fully supported by claude, kiro, gemini, agent-skills, openclaw, hermes, copilot-cowork, copilot-app. Partially supported: copilot, 
cursor, opencode, antigravity, codex, windsurf.
Some primitives are not supported: cursor (instructions); opencode (hooks); antigravity (instructions, hooks); windsurf (instructions)
[*] Validating 1 package...
[+] kilianpaquier/agent-rules (already in apm.yml)
[>] Installing 1 new package...
  [+] kilianpaquier/agent-rules @d2029530 (cached)
  |-- 1 instruction(s) integrated (11 adopted) -> .claude/rules/, .copilot/
  [+] <project root> (local)
  |-- (files unchanged)
[i] Cleaned 11 stale files from kilianpaquier/agent-rules
  [!] 1 dependency unpinned: kilianpaquier/agent-rules -- add #tag or #sha to prevent drift
[*] Installed 1 APM dependency (11 stale files cleaned) in 0.7s

❯ lla ~/.copilot/instructions
ls: cannot access '/home/kilianpaquier/.copilot/instructions': No such file or directory
❯ cat ~/.copilot/copilot-instructions.md
<!-- apm-managed: copilot-instructions.md -->
<!-- apm:source:kilianpaquier/agent-rules -->

Local build of this branch:

❯ ./dist/apm-linux-x86_64/apm install kilianpaquier/agent-rules -g --target claude,copilot
[i] Installing to user scope (~/.apm/)
[!] User-scope primitives are fully supported by claude, kiro, gemini, agent-skills, openclaw, hermes, copilot-cowork, copilot-app. Partially supported: copilot, cursor, opencode, antigravity, codex, windsurf.
Some primitives are not supported: cursor (instructions); opencode (hooks); antigravity (instructions, hooks); windsurf (instructions)
[*] Validating 1 package...
[+] kilianpaquier/agent-rules (already in apm.yml)
[>] Installing 1 new package...
  [+] kilianpaquier/agent-rules @d2029530 (cached)
  |-- 11 instruction(s) integrated (11 adopted) -> .claude/rules/, .copilot/instructions/
  [+] <project root> (local)
  |-- (files unchanged)
[i] Cleaned 1 stale file from kilianpaquier/agent-rules
  [!] 1 dependency unpinned: kilianpaquier/agent-rules -- add #tag or #sha to prevent drift
[*] Installed 1 APM dependency (1 stale file cleaned) in 0.8s.

❯ lla ~/.copilot/instructions
total 60
-rw-r--r--  1 kilianpaquier kilianpaquier 1533 Jul 19 00:12 docker-compose.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 2123 Jul 19 00:12 typescript.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 1238 Jul 19 00:12 terraform.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier  924 Jul 19 00:12 shell.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 1013 Jul 19 00:12 markdown.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier  542 Jul 19 00:12 makefile.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 1942 Jul 19 00:12 go-test.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 4258 Jul 19 00:12 go.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 7681 Jul 19 00:12 global.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 2157 Jul 19 00:12 gitlab-ci.instructions.md
-rw-r--r--  1 kilianpaquier kilianpaquier 1831 Jul 19 00:12 docker.instructions.md
drwxr-xr-x  2 kilianpaquier kilianpaquier 4096 Jul 19 00:12 .
drwxr-xr-x 10 kilianpaquier kilianpaquier 4096 Jul 19 00:12 ..
❯ lla ~/.copilot/copilot-instructions.md
ls: cannot access '/home/kilianpaquier/.copilot/copilot-instructions.md': No such file or directory

[kilianpaquier]

@microsoft-github-policy-service agree

[Copilot]

Pull request overview

This PR reverts the Copilot user-scope instructions behavior introduced in #1619 by restoring modular instruction deployment for the Copilot target at user scope (deploying *.instructions.md files under ~/.copilot/instructions/ instead of concatenating into ~/.copilot/copilot-instructions.md).

Changes:

• Remove the Copilot user-scope instruction concat override from the Copilot TargetProfile and revert to the standard github_instructions mapping.
• Delete the concat integration/sync implementation from InstructionIntegrator and simplify sync cleanup back to directory-based removal.
• Update unit/integration tests and the targets matrix docs to reflect modular user-scope Copilot instruction deployment.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tests/unit/integration/test_scope_integration.py	Updates expectations for Copilot user-scope instructions mapping (github_instructions).
tests/unit/integration/test_scope_install_uninstall.py	Updates user-scope install assertions to expect .copilot/instructions/ files rather than a single concat file.
tests/unit/integration/test_data_driven_dispatch.py	Adjusts for-scope filtering/mapping expectations for Copilot user-scope instructions.
tests/unit/install/test_install_copilot_user_instructions.py	Reworks acceptance tests to validate per-file deployment under .copilot/instructions/ and frontmatter preservation.
tests/integration/test_integration_runtime_coverage.py	Removes coverage tests specific to the deleted concat helpers and concat integration path.
src/apm_cli/integration/targets.py	Removes Copilot user-scope primitive override; updates Copilot user-scope behavior comments.
src/apm_cli/integration/instruction_integrator.py	Removes concat integration path and collapses sync cleanup logic to directory-prefix behavior.
docs/src/content/docs/reference/targets-matrix.md	Updates Copilot user-scope documentation to describe modular instructions under ~/.copilot/instructions/.

Comments suppressed due to low confidence (1)

src/apm_cli/integration/instruction_integrator.py:271

• sync_for_target() now only removes managed files under "//". If a user previously installed Copilot user-scope instructions with the old concat format, the lockfile can still contain ".copilot/copilot-instructions.md" (root file), and an uninstall with this code will never match the new prefix, leaving that legacy file behind. Consider adding a small legacy cleanup pass for that specific path when uninstalling copilot at user scope.

        return self.sync_remove_files(
            project_root,
            managed_files,
            prefix=prefix,
            legacy_glob_dir=legacy_dir,