feat: add responsive font sizing for mobile

- Add src/utils/responsive.js with fontSize() helper
- Mobile fonts scale 1.4x for better readability
- Update all scenes to use responsive font sizes
- Update deploy-k8s.sh with full deployment steps

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/scenes/TransitionScene.js

@@ -1,4 +1,5 @@
 import Phaser from 'phaser';
+import { fontSize } from '../utils/responsive.js';
 
 export default class TransitionScene extends Phaser.Scene {
     constructor() {
@@ -30,7 +31,7 @@ export default class TransitionScene extends Phaser.Scene {
 
         // Destination title
         this.add.text(400, 360, content.title, {
-            fontSize: '32px',
+            fontSize: fontSize(32),
             fill: '#ffffff',
             fontStyle: 'bold',
             stroke: '#000000',
@@ -39,7 +40,7 @@ export default class TransitionScene extends Phaser.Scene {
 
         // Journey description
         this.add.text(400, 430, content.description, {
-            fontSize: '18px',
+            fontSize: fontSize(18),
             fill: '#ffffff',
             align: 'center',
             wordWrap: { width: 660 }
@@ -48,12 +49,12 @@ export default class TransitionScene extends Phaser.Scene {
         // Fuel cost display (only if there's a cost)
         if (this.fuelCost > 0) {
             this.add.text(400, 500, `Fuel consumed: ${this.fuelCost} units`, {
-                fontSize: '16px',
+                fontSize: fontSize(16),
                 fill: '#ffff00'
             }).setOrigin(0.5);
         } else {
             this.add.text(400, 500, 'The wind carries your sails...', {
-                fontSize: '16px',
+                fontSize: fontSize(16),
                 fill: '#cccccc',
                 fontStyle: 'italic'
             }).setOrigin(0.5);
@@ -65,7 +66,7 @@ export default class TransitionScene extends Phaser.Scene {
         continueBtn.setStrokeStyle(3, 0xffffff);
 
         const btnText = this.add.text(400, 540, 'CONTINUE', {
-            fontSize: '20px',
+            fontSize: fontSize(20),
             fill: '#fff',
             fontStyle: 'bold'
         }).setOrigin(0.5);
@@ -265,7 +266,7 @@ export default class TransitionScene extends Phaser.Scene {
             const x = 200 + i * 200;
             const y = 80 + Math.random() * 40;
             const bird = this.add.text(x, y, 'v', {
-                fontSize: '20px',
+                fontSize: fontSize(20),
                 fill: '#ffffff'
             });