Add tap-controlled incremental space-knight game

Auto-flying knight, crystal zones, pirate/boss combat, shop upgrades,
falling/golden asteroids, particle juice, droid evolution, and a
supernova prestige cutscene, per the design spec.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D5SuZW1XGCkahPX7cHMoRP

src/game/types.ts

@@ -0,0 +1,99 @@
+export type UpgradeKey = 'crystal' | 'speed' | 'damage' | 'droid';
+
+export interface CrystalEntity {
+  id: number;
+  x: number;
+  y: number;
+  value: number;
+  radius: number;
+  rotation: number;
+  spin: number;
+  jitter: number[];
+}
+
+export interface EnemyEntity {
+  id: number;
+  x: number;
+  y: number;
+  hp: number;
+  maxHp: number;
+  speed: number;
+  radius: number;
+  isBoss: boolean;
+  state: 'chase' | 'fight';
+  wanderAngle: number;
+  jitter: number[];
+  hitFlash: number;
+}
+
+export interface DroidEntity {
+  id: number;
+  angleOffset: number;
+  cooldown: number;
+  laserTimer: number;
+}
+
+export interface AsteroidEntity {
+  id: number;
+  x: number;
+  y: number;
+  vx: number;
+  speed: number;
+  radius: number;
+  rotation: number;
+  spin: number;
+  jitter: number[];
+}
+
+export interface GoldenAsteroidEntity {
+  id: number;
+  x: number;
+  y: number;
+  vx: number;
+  vy: number;
+  radius: number;
+  rotation: number;
+  jitter: number[];
+}
+
+export interface Particle {
+  x: number;
+  y: number;
+  vx: number;
+  vy: number;
+  life: number;
+  maxLife: number;
+  size: number;
+  color: string;
+}
+
+export interface FloatingText {
+  x: number;
+  y: number;
+  vy: number;
+  life: number;
+  maxLife: number;
+  text: string;
+  color: string;
+}
+
+export interface GameSnapshot {
+  score: number;
+  zone: number;
+  crystalsInZone: number;
+  crystalsRequired: number;
+  darkMatter: number;
+  bossActive: boolean;
+  bossHp: number;
+  bossMaxHp: number;
+  pirateActive: boolean;
+  pirateHp: number;
+  pirateMaxHp: number;
+  levels: Record<UpgradeKey, number>;
+  costs: Record<UpgradeKey, number>;
+  canAfford: Record<UpgradeKey, boolean>;
+  droidCount: number;
+  canPrestige: boolean;
+  prestigeGain: number;
+  cutsceneActive: boolean;
+}