feat: migrate to DragonflyDB and clean up environment configuration

- Replace Redis with DragonflyDB for better performance and memory efficiency
- Remove redundant environment variables (POSTGRES_*, ENCRYPTION_KEY, OAUTH_SERVICE_URL)
- Consolidate database configuration to use single DB_* variables
- Use JWT_SECRET for both JWT tokens and encryption
- Remove PORT variable redundancy, use BACKEND_PORT consistently
- Clean up docker-compose configurations for dev/prod consistency
- Add DragonflyDB configuration with optimized memory usage
- Remove redis.conf as it's no longer needed
- Update health checks to use Redis-compatible CLI for DragonflyDB
- Add missing VITE_API_URL to production frontend
- Fix GitHub Actions to use correct go.sum path
- Clean up development directories and unused files

backend/middleware/cache.go

@@ -44,6 +44,12 @@ func CacheMiddleware(config CacheConfig) gin.HandlerFunc {
 			return
 		}
 
+		// Skip caching for auth/bootstrap requests and authenticated traffic.
+		if shouldSkipCache(c) {
+			c.Next()
+			return
+		}
+
 		// Generate cache key
 		cacheKey := generateCacheKey(c, config.KeyPrefix)
 
@@ -60,7 +66,7 @@ func CacheMiddleware(config CacheConfig) gin.HandlerFunc {
 
 		// Cache miss, continue with request
 		c.Header("X-Cache", "MISS")
-		
+
 		// Capture response
 		writer := &cachedResponseWriter{
 			ResponseWriter: c.Writer,
@@ -82,6 +88,20 @@ func CacheMiddleware(config CacheConfig) gin.HandlerFunc {
 	}
 }
 
+func shouldSkipCache(c *gin.Context) bool {
+	path := c.Request.URL.Path
+
+	if strings.HasPrefix(path, "/api/v1/auth/") {
+		return true
+	}
+
+	if c.GetHeader("Authorization") != "" || c.GetHeader("Cookie") != "" {
+		return true
+	}
+
+	return false
+}
+
 // generateCacheKey creates a unique cache key for the request
 func generateCacheKey(c *gin.Context, prefix string) string {
 	// Include path, query params, and user ID if available