Reduce status polling load and add 1Hz ready LED blink

src/webapp.py

@@ -2,6 +2,7 @@ import json
 import queue
 import subprocess
 import threading
+import time
 from typing import Any, Dict
 
 from flask import Flask, Response, jsonify, render_template, request, stream_with_context
@@ -24,6 +25,9 @@ class WebPortal:
         self.state = state
         self.network_manager = network_manager
         self.broadcaster = broadcaster
+        self._status_refresh_interval_s = 15.0
+        self._last_status_refresh_mono = 0.0
+        self._status_lock = threading.Lock()
         self.app = Flask(__name__, template_folder=template_folder, static_folder=static_folder)
         self._register_routes()
 
@@ -39,7 +43,11 @@ class WebPortal:
         @self.app.route("/api/status", methods=["GET"])
         def status() -> Response:
             try:
-                self.network_manager.refresh_state()
+                now = time.monotonic()
+                with self._status_lock:
+                    if now - self._last_status_refresh_mono >= self._status_refresh_interval_s:
+                        self.network_manager.refresh_state()
+                        self._last_status_refresh_mono = now
                 return jsonify(self.state.snapshot())
             except Exception as exc:
                 self.state.update_status("Status update failed", str(exc))