Implement shell completions for CLI (Workstream N-Completions)

Add `reviq completions bash/zsh` command with dynamic shell completions:

- Create bash-complete.ts entry point using stricli's proposeCompletions API
- Add completions command with bash and zsh support (fish planned)
- Extract app export to separate app.ts for shared imports
- Add @stricli/auto-complete dependency and __reviq_bash_complete bin entry

Also fix lint/type errors in api-server tests and helpers.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/api-server/src/__tests__/e2e/webauthn.test.ts

@@ -49,6 +49,8 @@ function createAPIContext(): APIContext {
     origin: TEST_RP.origin,
     allowedOrigins: [...TEST_RP.allowedOrigins],
     rpName: TEST_RP.rpName,
+    reqHeaders: new Headers(),
+    resHeaders: new Headers(),
   };
 }
 
@@ -69,7 +71,7 @@ function createAuthenticatedContext(
       isSuperuser: false,
     },
     session: {
-      id: 1,
+      id: "1",
       trustedMode: false,
       createdAt: new Date(),
     },