feat(vscode): extension VS Code native (intégration native, pas un webview)

Nouveau workspace packages/vscode (git-arboretum, privé, non publié sur npm), client REST/WS
réutilisant @arboretum/shared. Auth Authorization: Bearer sur REST et l'upgrade WS (via `ws`) ;
un client Node sans en-tête Origin passe le check Origin strict du serveur.

- Arbres temps réel : Repositories (repos → worktrees → sessions) et Groups, via le WebSocket.
- Terminaux natifs (vscode.Pseudoterminal) pour attacher/observer une session — rendu et
  scrollback de VS Code ; décodage UTF-8 streaming + comptabilité ACK dans des modules purs.
- Status bar (compteur waiting) + notifications natives sur passage en waiting, réponses Yes/No
  via la commande WS answer.
- Mutations git (create worktree, commit, push, promote), start/kill/hide/resume/fork, session
  de groupe ; conscience du workspace (reveal + start/create here).
- Bundle esbuild (format cjs, external vscode) inlinant @arboretum/shared → VSIX autonome.
  Logique réutilisable sans import vscode → testée par vitest (19 tests).
- CI : .gitea/workflows/vscode-release.yml package le VSIX sur tag vscode-vX.Y.Z (artefact +
  asset de release best-effort). build:vscode hors du build principal (comme le site).
- spikes/s5-vscode/STUDY.md : décision de conception (GO phasé A→D), marquée implémentée.

packages/vscode/test/store.test.ts

@@ -0,0 +1,103 @@
+import { describe, expect, it } from 'vitest';
+import type { RepoSummary, SessionSummary, WorktreeSummary } from '@arboretum/shared';
+import { Store } from '../src/state/store.js';
+
+function repo(id: string): RepoSummary {
+  return {
+    id,
+    path: `/code/${id}`,
+    label: id,
+    defaultBranch: 'main',
+    postCreateHooks: [],
+    preTrust: false,
+    createdAt: '2026-01-01T00:00:00Z',
+    valid: true,
+    hidden: false,
+  };
+}
+
+function worktree(repoId: string, path: string, branch: string): WorktreeSummary {
+  return {
+    repoId,
+    path,
+    branch,
+    head: 'abcdef0',
+    detached: false,
+    locked: false,
+    prunable: false,
+    isMain: branch === 'main',
+    git: { ahead: 0, behind: 0, dirtyCount: 0, upstream: null },
+    sessions: [],
+  };
+}
+
+function session(id: string, cwd: string, over: Partial<SessionSummary> = {}): SessionSummary {
+  return {
+    id,
+    cwd,
+    command: 'claude',
+    title: null,
+    status: 'running',
+    live: true,
+    createdAt: '2026-01-01T00:00:00Z',
+    endedAt: null,
+    exitCode: null,
+    clients: 0,
+    source: 'managed',
+    claudeSessionId: null,
+    pid: 123,
+    resumable: false,
+    attachable: true,
+    registryStatus: null,
+    ...over,
+  };
+}
+
+describe('Store', () => {
+  it('corrèle les sessions au worktree par cwd et filtre les externes', () => {
+    const store = new Store();
+    store.applyWorktree({ type: 'repo_update', repo: repo('app') });
+    store.applyWorktree({ type: 'worktree_update', repoId: 'app', worktree: worktree('app', '/code/app', 'main') });
+
+    store.applySession({ type: 'session_update', session: session('s1', '/code/app') });
+    store.applySession({ type: 'session_update', session: session('s2', '/code/app', { source: 'discovered' }) });
+
+    // externes masquées par défaut
+    expect(store.sessionsForWorktree('/code/app').map((s) => s.id)).toEqual(['s1']);
+    store.setShowExternalSessions(true);
+    expect(store.sessionsForWorktree('/code/app').map((s) => s.id).sort()).toEqual(['s1', 's2']);
+  });
+
+  it('liste les repos visibles, triés', () => {
+    const store = new Store();
+    store.applyWorktree({ type: 'repo_update', repo: { ...repo('b'), label: 'beta' } });
+    store.applyWorktree({ type: 'repo_update', repo: { ...repo('a'), label: 'alpha' } });
+    store.applyWorktree({ type: 'repo_update', repo: { ...repo('h'), label: 'hidden', hidden: true } });
+    expect(store.listRepos().map((r) => r.label)).toEqual(['alpha', 'beta']);
+  });
+
+  it('session_exit marque la session morte', () => {
+    const store = new Store();
+    store.applySession({ type: 'session_update', session: session('s1', '/x') });
+    store.applySession({ type: 'session_exit', sessionId: 's1', exitCode: 0, signal: null });
+    expect(store.getSession('s1')?.live).toBe(false);
+    expect(store.getSession('s1')?.status).toBe('exited');
+  });
+
+  it('waitingSessions ne retient que les sessions live en attente', () => {
+    const store = new Store();
+    store.applySession({ type: 'session_update', session: session('s1', '/x', { activity: 'waiting' }) });
+    store.applySession({ type: 'session_update', session: session('s2', '/y', { activity: 'busy' }) });
+    store.applySession({ type: 'session_update', session: session('s3', '/z', { activity: 'waiting', live: false, status: 'exited' }) });
+    expect(store.waitingSessions().map((s) => s.id)).toEqual(['s1']);
+  });
+
+  it('worktree_removed retire le worktree', () => {
+    const store = new Store();
+    store.applyWorktree({ type: 'repo_update', repo: repo('app') });
+    store.applyWorktree({ type: 'worktree_update', repoId: 'app', worktree: worktree('app', '/code/app-wt', 'feat') });
+    expect(store.listWorktrees('app')).toHaveLength(1);
+    store.applyWorktree({ type: 'worktree_removed', repoId: 'app', path: '/code/app-wt' });
+    expect(store.listWorktrees('app')).toHaveLength(0);
+  });
+});