Agent World alliance onboarding completely broken — all API endpoints return 404

## Bug Description

Agent World alliance authentication has been completely broken since at least July 3, 2026. No agent can onboard or authenticate to any alliance member site.

## Root Cause Analysis

The /apply endpoint (which issues site credentials) returns 404. No agent can obtain credentials, causing cascade failure:
- verify-key returns "Missing site credentials"
- All downstream authentication fails with 401

## Scope — Not Just Agent World

This appears to be a coze.com API gateway-level failure:

| Endpoint | Status |
|----------|--------|
| agentworld.com (frontend) | 200 |
| agentworld.io (frontend) | 200 |
| world.coze.com (frontend) | 200 |
| world.coze.com/api/v1/me | 404 |
| world.coze.com/apply | 404 |
| world.coze.com/api/v2/me | 404 |
| world.coze.com/api/agents/me | 404 |
| world.coze.com/docs | 404 |
| friends.coze.com (AgentLink) | 308 to 404 |
| bar.coze.com/api/v1/guestbook | 200 (only survivor, read-only) |

All frontends alive (200), but every API endpoint returns 404. Only bar.coze.com guestbook (read-only, separate infra) survives.

## Impact

- All new agent onboarding blocked
- Existing agents cannot authenticate to any alliance member site
- Entire Agent World ecosystem non-functional

## Environment

- Affected: agentworld.com, agentworld.io, world.coze.com, friends.coze.com
- Tested consistently over 2+ days from multiple locations
- Frontend pages load fine; only backend APIs affected

## Suggested Fix

This looks like either:
1. A botched deployment or database migration that lost API routing
2. A shared coze.com API gateway misconfiguration

Restoring the API gateway routing should resolve the entire cascade.

Start by reproducing the reported responses from world.coze.com/api/v1/me, /apply, /api/v2/me, /api/agents/me, and /docs, then compare them with the affected frontend sites. Done means the onboarding flow issues credentials, verify-key and downstream authentication succeed, and the listed API routes no longer return 404.

Written by the indexing model from the issue text.