Wire view-mode toggles (alt-view + coordinate grid) via new ViewModeController

Moves the AlternateViewEvent / ToggleCoordinateGridEvent subscriptions out of
ClientGameRunner into a dedicated controller in src/client/controllers/. Also
wires ToggleCoordinateGridEvent (M keybind) — previously emitted with no
listener — so the persistent coordinate-grid toggle works. Grid + alt-view
hide names only under alt-view; M keeps names visible.

src/client/render/gl/GameView.ts

@@ -371,6 +371,9 @@ export class GameView {
   setAltView(active: boolean): void {
     this.renderer?.setAltView(active);
   }
+  setGridView(active: boolean): void {
+    this.renderer?.setGridView(active);
+  }
   setShowPatterns(active: boolean): void {
     this.renderer?.setShowPatterns(active);
   }

src/client/render/gl/Renderer.ts

@@ -1176,8 +1176,10 @@ export class GPURenderer {
     this.worldTextPass.tick();
     this.worldTextPass.draw(cam, zoom);
 
-    if (this.gridView) this.coordinateGridPass.draw(cam, zoom);
-    if (pe.name && !this.gridView)
+    // Grid shows on either trigger; names hide only under alt-view (space
+    // hold), not under the persistent M-key gridView toggle.
+    if (this.gridView || this.altView) this.coordinateGridPass.draw(cam, zoom);
+    if (pe.name && !this.altView)
       this.namePass.draw(cam, this.nightCompositePass.getAmbient());
 
     this.radialMenuPass.draw();

src/client/render/gl/render-settings.json

@@ -255,7 +255,7 @@
     "gradientSolidEnd": 0.1
   },
   "altView": {
-    "gridFontSize": 16,
+    "gridFontSize": 24,
     "recolorStructures": true
   },
   "tileDrip": {