- Add interactive API Browser to Settings > API Keys

- New APIBrowser component with full OpenAPI schema integration
    - Fetches and parses /openapi.json automatically
    - Groups endpoints by API tags (printers, archives, settings, etc.)
    - Expandable endpoint sections with color-coded method badges
    - Path parameter, query parameter, and JSON body editors
    - Auto-populates request body with schema examples
    - Live API request execution with response display
    - Response shows status code, timing, and formatted JSON
    - Copy response button with clipboard fallback
    - Search to filter endpoints across all categories
    - Expand All / Collapse All buttons
    - Link to Swagger UI (/docs)

  - Two-column layout for API Keys tab
    - Left: API key management + webhook documentation
    - Right: API Browser with dedicated test key input

  - Parameter validation
    - Shows warning for missing required parameters
    - Validates before sending requests to avoid 422 errors

  - UX improvements
    - "Use in API Browser" button on newly created keys
    - Responsive layout (stacked on mobile, side-by-side on xl+)

scripts/mqtt_sniffer.py

@@ -14,7 +14,6 @@ Example:
 import json
 import ssl
 import sys
-import time
 from datetime import datetime
 
 import paho.mqtt.client as mqtt
@@ -56,7 +55,7 @@ def on_message(client, userdata, msg):
             print(f"\n{'='*80}")
             print(f"[{datetime.now().strftime('%H:%M:%S.%f')[:-3]}] *** CALIBRATION COMMAND: {command} ***")
             print(f"Topic: {msg.topic}")
-            print(f"Full payload:")
+            print("Full payload:")
             print(json.dumps(payload, indent=2))
             print(f"{'='*80}\n")
         else: