feat(git-status): configurable max repositories and git timeout; keep unreadable repos listed

Settings (per device): Git status: max repositories (1-50, default 12) and git timeout (5-120 s, default 30, was a fixed 10). Both go to /git-status and /git-diff as maxRepos / timeout query parameters, clamped server-side (an empty value means the default). A repository whose git status fails stays in the list with the reason instead of being dropped silently, shows as '? N' in the indicator, and the truncation line now names the limit and the setting. The discovery cache is keyed by the limit.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JrzFKEdBLwVfu6ev2ZscJS

docs/wiki/Settings-Reference.md

@@ -66,7 +66,11 @@ bottom bar, off by default and per device. It reads `● N` uncommitted files, `
 pushed, `⚠ N` merge conflicts, or `✓` when everything is committed and pushed. Click it for the
 Git window; see [Working With Files](Working-With-Files#git-changes). **Git status: group files
 by folder** (per device, on by default) shows changed files under collapsed folders in that
-window; off lists every file by its full path.
+window; off lists every file by its full path. **Git status: max repositories** (per device,
+1 to 50, default 12) is how many repositories the window lists when a session's folder holds
+several projects. **Git status: git timeout** (per device, 5 to 120 seconds, default 30) is how
+long one git command may run before that repository is reported as unreadable; raise it for
+repositories on a slow network share.
 
 Most default to off. The stock desktop header is system stats, File Viewer, and the gear.
 New header controls never appear on phones. Split is desktop-only regardless of this