feat(orchestrator): create_skill action + wire per-project watchers (§14.3)

- domain: OrchestratorCommand::CreateSkill with optional scope field
  (defaults to Project, case-insensitive, UnknownScope on bad value)
- application: dispatch CreateSkill through the CreateSkill use case
- app-tauri: build OrchestratorService and start/stop per-project request
  watchers on open/create/close_project (ensure/stop_orchestrator_watch)
- tests: domain validation, service dispatch, infra watcher e2e,
  app-tauri wiring lifecycle (idempotent, isolated, stop)

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

crates/app-tauri/tests/orchestrator_wiring.rs

@@ -0,0 +1,100 @@
+//! Integration test for the orchestrator wiring in the composition root
+//! (ARCHITECTURE §14.3).
+//!
+//! These tests prove that [`AppState`] actually *starts and stops* per-project
+//! orchestrator watchers — the gap that previously left the whole §14.3 feature
+//! dormant (the `OrchestratorService`/watcher existed but were never constructed
+//! at runtime). The per-file request→dispatch→response behaviour is covered by
+//! the infrastructure watcher tests; here we assert the lifecycle the open/close
+//! commands rely on: registration is idempotent, projects are isolated, and
+//! stopping unregisters.
+
+use std::path::PathBuf;
+
+use app_tauri_lib::state::AppState;
+use domain::ports::IdGenerator;
+use domain::project::{Project, ProjectPath};
+use domain::remote::RemoteRef;
+use domain::ProjectId;
+use infrastructure::UuidGenerator;
+
+/// A unique, absolute temp path (never written to at build time — the stores are
+/// lazy — so it need not exist).
+fn temp_path(tag: &str) -> PathBuf {
+    let ids = UuidGenerator::new();
+    std::env::temp_dir().join(format!("idea-orch-test-{tag}-{}", ids.new_uuid()))
+}
+
+/// Builds a domain [`Project`] rooted at a fresh temp path.
+fn make_project() -> Project {
+    let ids = UuidGenerator::new();
+    let root = temp_path("root");
+    Project::new(
+        ProjectId::from_uuid(ids.new_uuid()),
+        "demo",
+        ProjectPath::new(root.to_string_lossy().into_owned()).unwrap(),
+        RemoteRef::local(),
+        1_700_000_000_000,
+    )
+    .unwrap()
+}
+
+fn watcher_count(state: &AppState) -> usize {
+    state.orchestrator_watchers.lock().unwrap().len()
+}
+
+fn has_watcher(state: &AppState, id: &ProjectId) -> bool {
+    state.orchestrator_watchers.lock().unwrap().contains_key(id)
+}
+
+#[tokio::test]
+async fn ensure_watch_registers_a_watcher_and_is_idempotent() {
+    let state = AppState::build(temp_path("appdata"));
+    let project = make_project();
+
+    assert_eq!(watcher_count(&state), 0, "no watcher before open");
+
+    state.ensure_orchestrator_watch(&project);
+    assert!(has_watcher(&state, &project.id));
+    assert_eq!(watcher_count(&state), 1);
+
+    // Opening the same project again must not spawn a second watcher.
+    state.ensure_orchestrator_watch(&project);
+    assert_eq!(watcher_count(&state), 1, "ensure is idempotent per project");
+}
+
+#[tokio::test]
+async fn stop_watch_unregisters_the_watcher() {
+    let state = AppState::build(temp_path("appdata"));
+    let project = make_project();
+
+    state.ensure_orchestrator_watch(&project);
+    assert!(has_watcher(&state, &project.id));
+
+    state.stop_orchestrator_watch(&project.id);
+    assert!(!has_watcher(&state, &project.id), "watcher removed on close");
+    assert_eq!(watcher_count(&state), 0);
+
+    // Stopping an unknown project is a no-op (does not panic).
+    state.stop_orchestrator_watch(&project.id);
+}
+
+#[tokio::test]
+async fn watchers_are_isolated_per_project() {
+    let state = AppState::build(temp_path("appdata"));
+    let a = make_project();
+    let b = make_project();
+
+    state.ensure_orchestrator_watch(&a);
+    state.ensure_orchestrator_watch(&b);
+
+    assert_eq!(watcher_count(&state), 2);
+    assert!(has_watcher(&state, &a.id));
+    assert!(has_watcher(&state, &b.id));
+
+    // Closing one leaves the other running.
+    state.stop_orchestrator_watch(&a.id);
+    assert!(!has_watcher(&state, &a.id));
+    assert!(has_watcher(&state, &b.id));
+    assert_eq!(watcher_count(&state), 1);
+}