feat(ai-access): per-workspace Gitea bot + tenant-safe Coolify proxy + MCP

Ship Phases 1–3 of the multi-tenant AI access plan so an AI agent can
act on a Vibn workspace with one bearer token and zero admin reach.

Phase 1 — Gitea bot per workspace
- Add gitea_bot_username / gitea_bot_user_id / gitea_bot_token_encrypted
  columns to vibn_workspaces (migrate route).
- New lib/auth/secret-box.ts (AES-256-GCM, VIBN_SECRETS_KEY) for PAT at rest.
- Extend lib/gitea.ts with createUser, createAccessTokenFor (Sudo PAT),
  createOrgTeam, addOrgTeamMember, ensureOrgTeamMembership.
- ensureWorkspaceProvisioned now mints a vibn-bot-<slug> user, adds it to
  a Writers team (write perms only) on the workspace's org, and stores
  its PAT encrypted.
- GET /api/workspaces/[slug]/gitea-credentials returns a workspace-scoped
  bot PAT + clone URL template; session or vibn_sk_ bearer auth.

Phase 2 — Tenant-safe Coolify proxy + real MCP
- lib/coolify.ts: projectUuidOf, listApplicationsInProject,
  getApplicationInProject, TenantError, env CRUD, deployments list.
- Workspace-scoped REST endpoints (all filtered by coolify_project_uuid):
  GET/POST /api/workspaces/[slug]/apps/[uuid](/deploy|/envs|/deployments),
  GET /api/workspaces/[slug]/deployments/[deploymentUuid]/logs.
- Full rewrite of /api/mcp off legacy Firebase onto Postgres vibn_sk_
  keys, exposing workspace.describe, gitea.credentials, projects.*,
  apps.* (list/get/deploy/deployments, envs.list/upsert/delete).

Phase 3 — Settings UI AI bundle
- GET /api/workspaces/[slug]/bootstrap.sh: curl|sh installer that writes
  .cursor/rules, .cursor/mcp.json and appends VIBN_* to .env.local.
  Embeds the caller's vibn_sk_ token when invoked with bearer auth.
- WorkspaceKeysPanel: single AiAccessBundleCard with system-prompt block,
  one-line bootstrap, Reveal-bot-PAT button, collapsible manual-setup
  fallback. Minted-key modal also shows the bootstrap one-liner.

Ops prerequisites:
  - Set VIBN_SECRETS_KEY (>=16 chars) on the frontend.
  - Run /api/admin/migrate to add the three bot columns.
  - GITEA_API_TOKEN must be a site-admin token (needed for admin/users
    + Sudo PAT mint); otherwise provision_status lands on 'partial'.

Made-with: Cursor

app/api/admin/migrate/route.ts

@@ -187,6 +187,17 @@ export async function POST(req: NextRequest) {
     // this new UUID FK is the canonical link.
     `ALTER TABLE fs_projects ADD COLUMN IF NOT EXISTS vibn_workspace_id UUID REFERENCES vibn_workspaces(id) ON DELETE SET NULL`,
     `CREATE INDEX IF NOT EXISTS fs_projects_vibn_workspace_idx ON fs_projects (vibn_workspace_id)`,
+
+    // ── Per-workspace Gitea bot user (for direct AI access) ──────────
+    // Each workspace gets its own Gitea user with a PAT scoped to the
+    // workspace's org, so AI agents can `git clone` / push directly
+    // without ever touching the root admin token.
+    //
+    // Token is encrypted at rest with AES-256-GCM using VIBN_SECRETS_KEY.
+    // Layout: iv(12) || ciphertext || authTag(16), base64-encoded.
+    `ALTER TABLE vibn_workspaces ADD COLUMN IF NOT EXISTS gitea_bot_username TEXT`,
+    `ALTER TABLE vibn_workspaces ADD COLUMN IF NOT EXISTS gitea_bot_user_id INT`,
+    `ALTER TABLE vibn_workspaces ADD COLUMN IF NOT EXISTS gitea_bot_token_encrypted TEXT`,
   ];
 
   for (const stmt of statements) {