fix: resolve duplicate header and improve Redis management

- Dashboard: Remove redundant header (Layout already provides it)
- projectctl.sh: Add start_redis/stop_redis functions for automatic
  Redis lifecycle management on project start/stop
- rate_limiter.py: Add fallback to memory storage when Redis unavailable

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

backend/app/core/rate_limiter.py

@@ -5,6 +5,7 @@ This module provides rate limiting functionality to protect against
 brute force attacks and DoS attempts on sensitive endpoints.
 """
 
+import logging
 import os
 
 from slowapi import Limiter
@@ -12,10 +13,50 @@ from slowapi.util import get_remote_address
 
 from app.core.config import settings
 
-# Use memory storage for testing, Redis for production
-# This allows tests to run without a Redis connection
-_testing = os.environ.get("TESTING", "").lower() in ("true", "1", "yes")
-_storage_uri = "memory://" if _testing else settings.REDIS_URL
+logger = logging.getLogger(__name__)
+
+
+def _get_storage_uri() -> str:
+    """
+    Determine the appropriate storage URI for rate limiting.
+
+    Priority:
+    1. Use memory storage if TESTING environment variable is set
+    2. Try Redis if available
+    3. Fall back to memory storage if Redis is unavailable (with warning)
+
+    Note: Memory storage is acceptable for development but Redis should
+    be used in production for consistent rate limiting across workers.
+    """
+    # Use memory storage for testing
+    testing = os.environ.get("TESTING", "").lower() in ("true", "1", "yes")
+    if testing:
+        return "memory://"
+
+    # Try to connect to Redis
+    redis_url = settings.REDIS_URL
+    try:
+        import redis
+        r = redis.Redis(
+            host=settings.REDIS_HOST,
+            port=settings.REDIS_PORT,
+            db=settings.REDIS_DB,
+            socket_connect_timeout=1,
+        )
+        r.ping()
+        logger.info("Rate limiter using Redis storage")
+        return redis_url
+    except Exception as e:
+        logger.warning(
+            f"Redis unavailable for rate limiting ({e}). "
+            "Falling back to in-memory storage. "
+            "Note: In production, Redis should be running for consistent "
+            "rate limiting across multiple workers."
+        )
+        return "memory://"
+
+
+_storage_uri = _get_storage_uri()
 
 # Create limiter instance with appropriate storage
 # Uses the client's remote address (IP) as the key for rate limiting