User management: signing in is required before anything is loaded, the sign-in screen is drawn in the same canvas (user name, password as bullets, Enter moves on and submits) and the editor is built only after it; the API gained auth/session, auth/login and auth/logout while every other route answers 401 without a session, projects carry an owner and a foreign one comes back as 404, accounts live in data/users.json with a password hash and sessions as files in data/sessions with a sliding 30 days, so a build under the open tab does not sign anybody out; Logout sits at the far right of the toolbar and, as asked in the issue, does not reload the page: Editor.dispose() takes the editor down while the canvas stays, which is why the autosave, the focus handlers, the window listeners of the tilemap panel, the shortcuts and the plugins all got a way back; the tools sign in as e2e (tools/lib/auth.mjs, password from GAME_MAKER_E2E_PASSWORD or the git-ignored data/e2e-password.txt) and the browser gets the same session by cookie, new e2e module 45 covers the screen, the wrong pair, the bullets, logout without a reload and signing in again, new unit tests for HttpAuthStore and for what a session leaves behind (#177)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/ui/widgets/TextField.ts

@@ -19,8 +19,13 @@ export interface TextFieldOptions {
    * semantics, unlike `onChange`, which also fires when a click elsewhere takes the focus.
    */
   onSubmit?: (value: string) => void;
+  /** A password: drawn as bullets, and never on screen as itself. */
+  secret?: boolean;
 }
 
+/** What a masked field shows per character. */
+const BULLET = '•';
+
 /**
  * Single-line text input drawn in the canvas. Keyboard handling is delegated to the
  * KeyboardBridge while focused; this class only mirrors value, selection and caret.
@@ -42,6 +47,7 @@ export class TextField extends Widget implements TextEditTarget {
   private blinkTimer = 0;
   private dragSelecting = false;
   placeholder: string;
+  private readonly secret: boolean;
   onInput?: (value: string) => void;
   onChange?: (value: string) => void;
   onSubmit?: (value: string) => void;
@@ -53,6 +59,7 @@ export class TextField extends Widget implements TextEditTarget {
     this.onInput = options.onInput;
     this.onChange = options.onChange;
     this.onSubmit = options.onSubmit;
+    this.secret = options.secret ?? false;
     this.focusable = true;
     this.cursor = 'text';
     this.minHeight = Theme.controlHeight;
@@ -207,8 +214,14 @@ export class TextField extends Widget implements TextEditTarget {
     if (ui().focus.focused === this) ui().focus.blur();
   }
 
+  /** What the field puts on screen for `text`: the text itself, or one bullet per character. */
+  protected shown(text: string): string {
+    return this.secret ? BULLET.repeat(text.length) : text;
+  }
+
+  // Measured on what is drawn, so caret and selection of a masked field sit on the bullets.
   private textWidth(text: string): number {
-    return CanvasTextMetrics.measureText(text, this.textNode.style).width;
+    return CanvasTextMetrics.measureText(this.shown(text), this.textNode.style).width;
   }
 
   /** Character index closest to a local x coordinate. */
@@ -258,7 +271,7 @@ export class TextField extends Widget implements TextEditTarget {
       .rect(1, 1, this.w - 2, this.h - 2)
       .fill(0xffffff);
 
-    this.textNode.text = this.valueText;
+    this.textNode.text = this.shown(this.valueText);
     this.placeholderNode.text = this.valueText ? '' : this.placeholder;
 
     // Horizontal scroll so the caret stays visible.