merge: AgentProject membership — the junction is now load-bearing

Merges feat/agent-project-membership (task 166/152). An agent can finally join
many projects: membership routes, per-membership role and optional brain
override, chat resolving context from the membership, and CLI attach-agent /
detach-agent / get memberships. The legacy Agent.projectId fallback is kept for
this release as the schema comment promises.

Conflict resolved in main.ts: that branch added its RBAC case to
mapUrlToPermission inline, while this branch had extracted the function to
middleware/url-permission.ts so it could be tested. Kept the extraction and
ported the case into it — joining a team is `edit:agents:<name>`, not
`create:agents`, which is the authority to mint a whole agent.

Also fixes something the extraction makes possible. security.test.ts contained a
hand-copied reproduction of mapUrlToPermission, because main.ts self-invokes
main() and nothing in it was importable. A security test asserting against a
copy stops testing the system the moment the real one changes, and this copy had
already drifted. It now imports the real function; all 18 assertions still pass,
against the code that actually runs.

Local: build clean, workspace 2550 passed, lint unchanged at 794 errors.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N4wNHWf7xSwnZCWpJcyv9p

.taskmaster/tasks/task_086.md

@@ -0,0 +1,57 @@
+# Task ID: 86
+
+**Title:** Implement Hot-Reload for ProxyModels
+
+**Status:** done
+
+**Dependencies:** 78 ✓
+
+**Priority:** medium
+
+**Description:** Add file watching for ~/.mcpctl/proxymodels/ to automatically reload proxymodel definitions when they change.
+
+**Details:**
+
+Create `src/mcplocal/src/proxymodel/model-watcher.ts`:
+
+```typescript
+import { watch, FSWatcher } from 'fs';
+import { join } from 'path';
+import { readFile } from 'fs/promises';
+import { parse as parseYaml } from 'yaml';
+import { ProxyModelSchema } from './schema';
+
+const PROXYMODELS_DIR = join(process.env.HOME ?? '', '.mcpctl', 'proxymodels');
+let watcher: FSWatcher | null = null;
+const modelUpdateCallbacks: Set<() => void> = new Set();
+
+export function onModelUpdate(callback: () => void): () => void {
+  modelUpdateCallbacks.add(callback);
+  return () => modelUpdateCallbacks.delete(callback);
+}
+
+export function startModelWatcher(): void {
+  if (watcher) return;
+  
+  try {
+    watcher = watch(PROXYMODELS_DIR, async (eventType, filename) => {
+      if (!filename || (!filename.endsWith('.yaml') && !filename.endsWith('.yml'))) return;
+      
+      console.info(`[proxymodel] Model file ${filename} changed, reloading...`);
+      
+      // Notify all subscribers to reload their models
+      for (const cb of modelUpdateCallbacks) {
+        try { cb(); } catch (err) { console.error('Model update callback failed:', err); }
+      }
+    });
+  } catch {
+    // Directory doesn't exist
+  }
+}
+```
+
+Integrate with router to reload proxymodels when files change.
+
+**Test Strategy:**
+
+Integration tests: modify a proxymodel YAML and verify changes take effect, add a new proxymodel and verify it becomes available, invalid YAML logs error but doesn't crash.