feat: replace browser dialogs with in-game naming screen + notifications

Remove prompt() and alert() calls that broke game immersion. Add:
- Pokemon-style naming screen with character grid + direct typing
- Canvas-rendered notification toasts (with fade-out animation)
- Both render on top of workshop AND world mode canvases
- Workshop keyboard handler yields to naming screen when active

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

js/events.js

@@ -11,6 +11,7 @@ import { saveState, loadState, exportAsFile, importFromFile } from './saveLoad.j
 import { enterComponentEditor, editComponentBlueprint, exitComponentEditor, updateComponentButtons, setResizeCallback } from './components.js';
 import { getExampleList, loadExample } from './examples.js';
 import { createBusFromCut } from './bus.js';
+import { isNamingActive, handleNamingInput } from './world/inventory.js';
 
 const PAN_SPEED = 40;
 
@@ -325,6 +326,13 @@ export function initEvents() {
     const keysDown = new Set();
 
     document.addEventListener('keydown', e => {
+        // In-game naming screen takes priority over circuit editor
+        if (isNamingActive()) {
+            e.preventDefault();
+            handleNamingInput(e.key);
+            return;
+        }
+
         keysDown.add(e.key);
 
         if (e.key === 'Delete' || e.key === 'Backspace') {