fix(map3d): simplify projection loading release condition

apps/web/src/widgets/map3d/Map3D.tsx

@@ -605,7 +605,7 @@ export function Map3D({
             setProjectionLoading(false);
             console.warn("Projection loading fallback timeout reached.");
           }
-        }, 18000);
+        }, 3000);
       } else {
         clearProjectionBusyTimer();
       }
@@ -862,6 +862,41 @@ export function Map3D({
     const maxRetries = 18;
     const isTransition = projectionPrevRef.current !== projection;
     projectionPrevRef.current = projection;
+    let settleScheduled = false;
+    let settleCleanup: (() => void) | null = null;
+
+    const startProjectionSettle = () => {
+      if (!isTransition || settleScheduled) return;
+      settleScheduled = true;
+
+      const finalize = () => {
+        if (!cancelled && isTransition) setProjectionLoading(false);
+      };
+
+      const finalizeSoon = () => {
+        if (cancelled || !isTransition || projectionBusyRef.current === false) return;
+        if (!map.isStyleLoaded()) {
+          requestAnimationFrame(finalizeSoon);
+          return;
+        }
+        requestAnimationFrame(() => requestAnimationFrame(finalize));
+      };
+
+      const onIdle = () => finalizeSoon();
+      try {
+        map.on("idle", onIdle);
+        const styleReadyCleanup = onMapStyleReady(map, finalizeSoon);
+        settleCleanup = () => {
+          map.off("idle", onIdle);
+          styleReadyCleanup();
+        };
+      } catch {
+        requestAnimationFrame(finalize);
+        settleCleanup = null;
+      }
+
+      finalizeSoon();
+    };
 
     if (isTransition) setProjectionLoading(true);
 
@@ -985,17 +1020,7 @@ export function Map3D({
         // ignore
       }
       if (isTransition) {
-        const mercatorReady = projection === "mercator" && !!overlayRef.current;
-        const globeReady = projection === "globe" && !!map.getLayer("deck-globe");
-        if (mercatorReady || globeReady) {
-          setProjectionLoading(false);
-        } else if (!cancelled && retries < maxRetries) {
-          retries += 1;
-          window.requestAnimationFrame(() => syncProjectionAndDeck());
-          return;
-        } else {
-          setProjectionLoading(false);
-        }
+        startProjectionSettle();
       }
       pulseMapSync();
     };
@@ -1007,6 +1032,7 @@ export function Map3D({
       const stop = onMapStyleReady(map, syncProjectionAndDeck);
       return () => {
         cancelled = true;
+        if (settleCleanup) settleCleanup();
         stop();
         if (isTransition) setProjectionLoading(false);
       };
@@ -1014,6 +1040,7 @@ export function Map3D({
 
     return () => {
       cancelled = true;
+      if (settleCleanup) settleCleanup();
       if (isTransition) setProjectionLoading(false);
     };
   }, [projection, clearGlobeNativeLayers, ensureMercatorOverlay, removeLayerIfExists, setProjectionLoading]);