feat: add Recovery middleware for panic handling with verbose logging

backend/internal/api/middleware/recovery.go

@@ -0,0 +1,27 @@
+package middleware
+
+import (
+    "log"
+    "net/http"
+    "runtime/debug"
+
+    "github.com/gin-gonic/gin"
+)
+
+// Recovery logs panic information. When verbose is true it logs stacktraces
+// and basic request metadata for debugging.
+func Recovery(verbose bool) gin.HandlerFunc {
+    return func(c *gin.Context) {
+        defer func() {
+            if r := recover(); r != nil {
+                if verbose {
+                    log.Printf("PANIC: %v\nRequest: %s %s\nHeaders: %v\nStacktrace:\n%s", r, c.Request.Method, c.Request.URL.String(), c.Request.Header, debug.Stack())
+                } else {
+                    log.Printf("PANIC: %v", r)
+                }
+                c.AbortWithStatusJSON(http.StatusInternalServerError, gin.H{"error": "internal server error"})
+            }
+        }()
+        c.Next()
+    }
+}