fix(extraction): detect untracked files inside untracked directories (#1213)

[maxmilian]

Summary

Fixes #1213. codegraph sync silently skipped source files that live inside an untracked directory, reporting "Already up to date" and never picking them up (the file watcher missed them too).

Root cause

git status --porcelain --no-renames collapses an entirely-untracked directory into a single ?? frontend/ entry instead of listing the files inside it. collectGitStatus (src/extraction/index.ts) treats such ?? dir/ entries as possible embedded git repos and recurses via findNestedGitRepos — which only returns directories that are themselves git repos. A plain untracked directory has none, so its source files are never added to changes.added.

(The reporter's diagnosis was against v1.3.0, where the entry was simply skipped; on main the untracked-dir handling now exists but only covers embedded repos, so the same files still slip through.)

Fix

Add -uall so git lists individual untracked files (?? frontend/app.js) rather than collapsing the directory. Verified that nested untracked git repos still collapse to ?? repo/ even with -uall — git never crosses a repo boundary — so the existing embedded-repo recursion is unaffected.

One-line behavior change; root-cause analysis and the -uall fix were suggested by the reporter in #1213.

Tests

getGitChangedFiles is exported and covered by two regression tests:

• source files inside a fully-untracked directory are detected (the bug);
• an untracked embedded git repo is still recursed into (guards against an -uall regression).

Both pass; tsc --noEmit is clean; the existing sync / multi-repo-workspace / worktree-detection suites remain green.