feat(docker): docker-hosts CRUD, docker-link, and quick-start branch

- case-routes: GET/POST/PUT/DELETE /api/docker-hosts, POST /api/cases/docker-link
  (creates workspace, probes daemon + tmux-in-image), docker listing in
  GET /api/cases, docker-unlink (best-effort docker rm -f) in DELETE, single GET
- session-routes: /api/quick-start docker branch (rejects envOverrides/effort/
  per-CLI config, probes availability + tmux, casePath=hostWorkspacePath, seeds
  resume id, scaffolds hooks+CLAUDE.md if missing, threads docker into Session,
  Ralph auto-config skipped for docker)
- CaseInfo gains location:'docker' + docker{} block
- typecheck clean; 157 route+docker tests pass

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

src/types/api.ts

@@ -124,7 +124,7 @@ export interface CaseInfo {
   /** Whether CLAUDE.md exists */
   hasClaudeMd?: boolean;
   /** Case storage/execution location */
-  location?: 'local' | 'linked-local' | 'remote';
+  location?: 'local' | 'linked-local' | 'remote' | 'docker';
   /** Whether this is a linked local folder */
   linked?: boolean;
   /** Remote case metadata for display and session creation */
@@ -134,6 +134,14 @@ export interface CaseInfo {
     username: string;
     path: string;
   };
+  /** Docker case metadata for display and session creation */
+  docker?: {
+    hostId: string;
+    container: string;
+    image?: string;
+    path: string;
+    network?: string;
+  };
 }
 
 // ========== Error Handling Utilities ==========