Require the hook-event secret unconditionally, not only under a managed tunnel

COD-54 gated the /api/hook-event + /api/status-telemetry localhost bypass
behind the shared X-Codeman-Hook-Secret only WHILE a managed tunnel was
running, keeping a plain localhost bypass otherwise. But Codeman can't detect
a user's OWN loopback reverse proxy (their own `cloudflared --url`,
`tailscale serve`, nginx -> 127.0.0.1), which proxies internet traffic into
the loopback origin with req.ip === 127.0.0.1 — so that setup kept the unsafe
plain bypass.

Require the secret on the loopback bypass unconditionally. Managed-session
hooks already always present it (X-Codeman-Hook-Secret from
$CODEMAN_HOOK_SECRET_FILE, generated for every instance), so the legitimate
hook channel is unaffected; only the previously-unguarded own-proxy path is
now rejected. Drops the now-unused getTunnelRunning param from
registerAuthMiddleware.

Tests: cod54-hook-event-auth (tunnel-down now also requires the secret, plus
a good-secret positive case); auth-security (hook tests present the secret to
reach schema validation).

test/auth-security.test.ts

@@ -14,6 +14,7 @@ import { describe, it, expect, beforeAll, afterAll, beforeEach, afterEach, vi }
 import { WebServer } from '../src/web/server.js';
 import { TmuxManager } from '../src/tmux-manager.js';
 import { SettingsUpdateSchema } from '../src/web/schemas.js';
+import { getHookSecret, HOOK_SECRET_HEADER } from '../src/config/hook-secret.js';
 
 const AUTH_PORT = 3160;
 const NOAUTH_PORT = 3161;
@@ -250,28 +251,28 @@ describe('Auth Security', () => {
   });
 
   describe('Hook Event Endpoint', () => {
-    it('should allow hook events from localhost without auth', async () => {
+    it('should allow hook events from localhost with the hook secret (no Basic auth)', async () => {
       const res = await fetch(`${baseUrl}/api/hook-event`, {
         method: 'POST',
-        headers: { 'Content-Type': 'application/json' },
+        headers: { 'Content-Type': 'application/json', [HOOK_SECRET_HEADER]: getHookSecret() },
         body: JSON.stringify({
           event: 'stop',
           sessionId: 'nonexistent-session',
           data: {},
         }),
       });
-      // Should pass auth (localhost bypass) but may 404 on session — that's fine
-      // The key assertion is it does NOT return 401
+      // Should pass auth (localhost bypass + hook secret) but may 404 on session — that's fine.
+      // The key assertion is it does NOT return 401 (COD-91: secret required even with no tunnel).
       expect(res.status).not.toBe(401);
     });
 
     it('should reject hook events with invalid schema', async () => {
       const res = await fetch(`${baseUrl}/api/hook-event`, {
         method: 'POST',
-        headers: { 'Content-Type': 'application/json' },
+        headers: { 'Content-Type': 'application/json', [HOOK_SECRET_HEADER]: getHookSecret() },
         body: JSON.stringify({ invalid: 'data' }),
       });
-      // Schema validation should catch this
+      // Past the auth gate (valid secret) → schema validation should catch this (not a 401).
       expect(res.status).not.toBe(401); // Not an auth error
     });
   });

test/cod54-hook-event-auth.test.ts

@@ -4,15 +4,19 @@
  * The `/api/hook-event` localhost bypass let tunnel traffic (cloudflared
  * --url http://127.0.0.1:port) reach the loopback origin with req.ip ===
  * 127.0.0.1 and drive respawn/Ralph signals unauthenticated. The fix gates
- * the bypass behind a shared hook secret WHEN A TUNNEL IS RUNNING, while
- * keeping the plain localhost bypass for the normal loopback-only case so
- * already-deployed (pre-secret) hooks and the loop's own channel keep working.
+ * the bypass behind a shared hook secret. COD-91 makes that requirement
+ * UNCONDITIONAL — the loopback bypass requires the secret whether or not a
+ * managed tunnel is running, because Codeman can't detect a user's own loopback
+ * reverse proxy (own cloudflared / `tailscale serve` / nginx → 127.0.0.1).
+ * Managed-session hooks always present the secret, so the legitimate channel
+ * keeps working.
  *
  * Tests:
  *  - tunnel running + no secret  → 401 (closes the hole)
  *  - tunnel running + bad secret → 401
  *  - tunnel running + good secret → not 401 (allowed)
- *  - tunnel NOT running + no secret → not 401 (back-compat regression guard)
+ *  - tunnel NOT running + no secret → 401 (COD-91: secret required unconditionally)
+ *  - tunnel NOT running + good secret → not 401 (allowed)
  *  - rate limiting: rapid unauthorized hook POSTs eventually 429
  *
  * Port: 3230 (tunnel-running), 3231 (tunnel-down), 3232 (rate-limit)
@@ -83,7 +87,7 @@ describe('COD-54 hook-event auth — tunnel running requires secret', () => {
   });
 });
 
-describe('COD-54 hook-event auth — tunnel down keeps localhost bypass (back-compat)', () => {
+describe('COD-91 hook-event auth — tunnel down ALSO requires the secret', () => {
   let server: WebServer;
   let baseUrl: string;
   let isRunningSpy: ReturnType<typeof vi.spyOn>;
@@ -105,8 +109,13 @@ describe('COD-54 hook-event auth — tunnel down keeps localhost bypass (back-co
     delete process.env.CODEMAN_USERNAME;
   });
 
-  it('still allows a localhost hook POST WITHOUT a secret (existing hooks + loop channel keep working)', async () => {
+  it('rejects a localhost hook POST WITHOUT a secret even with no tunnel (COD-91)', async () => {
     const res = await postHook(baseUrl);
+    expect(res.status).toBe(401);
+  });
+
+  it('allows a localhost hook POST WITH the correct secret when no tunnel is running', async () => {
+    const res = await postHook(baseUrl, { [HOOK_SECRET_HEADER]: getHookSecret() });
     expect(res.status).not.toBe(401);
   });
 });