fix(ui): make diff-stat parsing locale-safe and dedupe the two parsers

TaskRowViewModel had its own ParseDiffStat expecting "+12"/"-3" tokens that
`git diff --stat` never emits, so the row badge always showed 0/0. Meanwhile
DetailsIslandViewModel's parser matched only the English words
"insertion"/"deletion", so it broke on a localized git (e.g. German Windows:
"Einfügung(en)"/"Löschung(en)").

Row and detail badge now share one parser, anchored on git's untranslated
(+)/(-) suffix instead of the language-dependent word before it, so it reads
correctly in any locale. Also corrected the Worker CLAUDE.md's branch-name
claim (`claudedo/{taskId[:8]}`) to match the actual full-GUID branch name.

src/ClaudeDo.Worker/CLAUDE.md

@@ -130,7 +130,7 @@ Full flow, invariants, and model/effort/max-turns resolution (including the low-
 - **ClaudeProcess** — spawns `claude -p --output-format stream-json --verbose --permission-mode auto` (or whatever app settings specify). Prompt via stdin, NDJSON from stdout. CancellationToken kills the process tree. Resolves `_cfg.ClaudeBin` via `ExecutableResolver` (`ClaudeDo.Data`, shared with `ClaudeCliPreflight` and the Installer's checks) before spawning — a `.cmd`/`.bat` shim (e.g. an npm-installed `claude`) is launched through `cmd.exe /c` since `UseShellExecute = false` can't exec a shim directly; a resolved `.exe` starts exactly as before. Throws if nothing resolves. *(Not yet on `main` — see `Environment Checks` in `ClaudeDo.Installer/CLAUDE.md`.)*
 - **ClaudeArgsBuilder** — `--model`, `--effort`, `--max-turns`, `--append-system-prompt`, `--agents`, `--json-schema`, `--resume`
 - **StreamAnalyzer** — parses NDJSON; extracts session_id, token counts, turn counts, result text, structured output. Replaced MessageParser.
-- **WorktreeManager** — worktrees on `claudedo/{taskId[:8]}` branches; commits with semantic messages, updates DB with head commit + diff stats
+- **WorktreeManager** — worktrees on `claudedo/{id}` branches (full task GUID, dashes stripped — a prefix isn't enough to rule out collisions); commits with semantic messages, updates DB with head commit + diff stats
 - **CommitMessageBuilder** — `{commitType}(slug): title\n\ndescription\n\nClaudeDo-Task: taskId`; `BuildMerge` is the merge-commit variant (`{commitType}(slug): merge title` + trailer). **Every merge caller passes a blank commit message on purpose** — `TaskMergeService` fills in `BuildMerge` from the task's commit type and its list's name, which is the only place that knows both. Don't reintroduce a caller-side literal.
 - **TaskResetService** — discards a failed task's worktree, resets the row to Idle, preserves run history
 - **AgentFileService** — manages `~/.claudeDo/agents/*.md`; list/refresh via SignalR