Motivation

• Provide richer per-file Git insights in the editor so users can see tracked/untracked and ignored status, last commit info, line diff stats and a readable before/after diff view.
• Allow fast feedback loops by letting users inject comments from the editor (Preview/Diff) directly into the agent chat as Regarding \\[file-path]\: [comment] and refresh git info after saves.

Description

• Backend: added helpers _is_tracked_file, _is_ignored_file, _parse_diff_blocks, and a new get_repository_file_git_details(repo_name, file_path) that returns tracked/ignored flags, lineStats, last commit metadata, last modified, line count and parsed diff blocks; handles untracked files by synthesizing an all-added block. (file: packages/pybackend/repository_service.py)
• Backend: exposed a new endpoint GET /api/repositories/{name}/git/file?path=... that returns the per-file git details. (file: packages/pybackend/app.py)
• Frontend API: added RepositoryFileGitDetails type and api.getRepositoryFileGitDetails(name, filePath) client method. (file: packages/frontend/src/hooks/useApi.ts)
• Frontend UI: updated RepositoryPage to show a top “Git File Info” panel and a conditional “Diff View” (before/after) when a file is opened and git is available, added Comment buttons on Preview and Diff panels that open a modal and inject Regarding \\[relative-file-path]\: [user-comment] into the agent chat, and refreshed file/git metadata after saving. (file: packages/frontend/src/pages/RepositoryPage.tsx)
• Styling: added CSS for the diff grid/columns to packages/frontend/src/styles/index.css.
• Tests: added unit tests for get_repository_file_git_details covering tracked and untracked file behavior. (file: packages/pybackend/tests/unit/test_repository_service.py)

Testing

• Ran backend unit tests with python -m pytest packages/pybackend/tests/unit/test_repository_service.py and related focused runs; backend tests passed (17 passed initially; selected file-git-detail tests passed later).
• Ran frontend unit test file src/components/GitTab.test.tsx with npm run -w packages/frontend test -- src/components/GitTab.test.tsx and it passed (1 file, 2 tests passed).
• Built the frontend with npm run -w packages/frontend build and the build succeeded.
• One attempted frontend test run using an invalid Vitest flag (--runInBand) failed due to the unknown option; this was a CLI invocation issue and not a code test failure.

Codex Task