test(tui): expand repository map coverage

[yswcyswc]

Issue for this PR

Related to #12. Builds on merged #24.

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Tests
• Documentation

What does this PR do?

The repository map could miss files read in the current session when read returned absolute paths, omit those files from model naming examples, or show more than 20 subgroups in the overflow group. This PR fixes those cases, adds focused unit and integration tests, and documents how to use and test /group in UserGuide.md.

How did you verify your code works?

• Unit: packages/tui/test/util/repository-functionality.test.ts checks layouts, 30-group and 20-subgroup limits, overflow file preservation, prompt bounds, and naming fallback. packages/tui/test/util/referenced-file.test.ts checks completed reads, excluded results, path conversion, and command registration.
• Integration: packages/tui/test/integration/repository-map.test.ts passes session read records through file collection, grouping, and naming/explanation prompts. It checks that repeated reads count once and that a read file remains prompt evidence.
• End-to-end (manual): UserGuide.md gives the full Learn-mode workflow; feat(tui): group files based on functionality for repository learning #18 and feat(tui): add context-aware repository group explanations #24 contain UI screenshots and a recording. Automated TUI E2E coverage is added separately in test(tui): verify group map navigation and explanations #29.
• From packages/tui: 225 passed, 1 skipped, 0 failed; bun typecheck and git diff --check passed. CI passed for this PR.

These tests match #12's grouping, limits, prioritization, and fallback criteria. The manual workflow checks model output and UI behavior that the unit and integration tests cannot.

Screenshots / recordings

Earlier packages/tui test run: 224 passed, 1 skipped, 0 failed. The new integration test brings the current result to 225 passed, 1 skipped, 0 failed.

The existing /group recording is linked in #18, and the explanation screenshot is in #24.

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[ItsJayYip]

Looks good! I like that you added tests for the group limits and made sure files don't get dropped when those limits are reached. One thing we could also test is what happens when the same file is read multiple times in a session. Otherwise, I think this works.