Make API endpoints compatible with Vultr API v2 format

- Change auth from X-API-Key header to Authorization: Bearer format
- Add /v2 prefix to all endpoints to match Vultr API URL structure
- Fix router paths (dns, firewall) to avoid duplicate path segments
- Split VPC 2.0 into separate router at /v2/vpc2

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

server/deps.py

@@ -1,20 +1,33 @@
 """Dependencies for FastAPI"""
 import os
-from fastapi import HTTPException, Security
-from fastapi.security import APIKeyHeader
+from fastapi import HTTPException, Header
+from typing import Optional
 
 from vultr_api import VultrClient
 
-API_KEY_HEADER = APIKeyHeader(name="X-API-Key", auto_error=False)
 VULTR_API_KEY = os.environ.get("VULTR_API_KEY")
 
 
-def get_client(api_key: str = Security(API_KEY_HEADER)) -> VultrClient:
-    """Get VultrClient instance with API key from header or environment"""
-    key = api_key or VULTR_API_KEY
+def get_client(authorization: Optional[str] = Header(None)) -> VultrClient:
+    """
+    Get VultrClient instance with API key from Authorization header or environment.
+
+    Supports Vultr API compatible format:
+        Authorization: Bearer YOUR_API_KEY
+    """
+    key = None
+
+    # Parse "Authorization: Bearer API_KEY" header
+    if authorization and authorization.startswith("Bearer "):
+        key = authorization[7:]  # Remove "Bearer " prefix
+
+    # Fallback to environment variable
+    if not key:
+        key = VULTR_API_KEY
+
     if not key:
         raise HTTPException(
             status_code=401,
-            detail="API key required. Set X-API-Key header or VULTR_API_KEY env var"
+            detail="API key required. Use 'Authorization: Bearer YOUR_API_KEY' header or set VULTR_API_KEY env var"
         )
     return VultrClient(api_key=key)