add clide status orientation snapshot; close Epic C (T-221)

clide status returns a one-shot snapshot for an orienting agent: the
workspace root, a git summary (branch/ahead/behind/clean/counts), the
active editor buffer + selection, the read-only readers' viewed docs
(new ReaderNavRegistry.currentByReader, the T-220 fold), focusedFile,
the live view-pane list (T-219), and the layout (slots + visibility +
focus mode). Previously 'status' was an unknown command (exit 3).

The verb handler (status_command.dart) is a thin Flutter-free wrapper;
the snapshot is assembled in main.dart where the live kernel + subsystem
state is in scope, with readerNav captured post-boot. Composite shape is
verified live; the pieces are unit-tested.

Closes T-221 and T-218 (Epic C) under T-208 'Give Claude hands' --
the observe half of D-6 parity is now in place.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/src/daemon/status_command.dart

@@ -0,0 +1,21 @@
+/// Registers the `status` command — a one-shot orientation snapshot
+/// (T-221, Gap 6 of self-analysis.md). It is the natural first call an
+/// agent makes: active pane, focused file + selection, git summary, and
+/// layout, in one round-trip, with exit 0.
+///
+/// The handler is intentionally thin: the snapshot is assembled by the
+/// caller (main.dart), which holds the live kernel + subsystem state
+/// (PanelRegistry, LayoutArrangement, EditorRegistry, GitClient,
+/// ReaderNavRegistry). This file just exposes the verb and wraps the
+/// assembled map, so it stays Flutter-free and trivially testable.
+library;
+
+import '../ipc/envelope.dart';
+import 'dispatcher.dart';
+
+/// Builds the orientation snapshot at request time. Returns a JSON-able map.
+typedef StatusSnapshot = Future<Map<String, Object?>> Function();
+
+void registerStatusCommand(DaemonDispatcher d, StatusSnapshot snapshot) {
+  d.register('status', (req) async => IpcResponse.ok(id: req.id, data: await snapshot()));
+}