Add version-based cache invalidation for voice data

Users with old cached voice data need to see the new models (tts-1-silero,
tts-1-kokoro). Added a cache version system that automatically invalidates
old cache when we update the voice models.

Changes:
- Added cacheVersionKey to track cache format version
- Set currentVersion to '2' (increment when voice models change)
- Cache is invalidated if version doesn't match
- Old cache entries are cleaned up automatically
- Users will automatically fetch fresh voice data on next modal open

public/src/tts-modal.js

@@ -9,20 +9,30 @@ async function populateVoiceDropdown(voiceSelection) {
 	// Check cache first (1 minute expiration)
 	const cacheKey = 'uncloseai_voices_cache';
 	const cacheTimeKey = 'uncloseai_voices_cache_time';
+	const cacheVersionKey = 'uncloseai_voices_cache_version';
 	const cacheExpiration = 60000; // 1 minute in milliseconds
+	const currentVersion = '2'; // Increment this when voice models change
 
 	try {
 		const cachedTime = localStorage.getItem(cacheTimeKey);
 		const cachedVoices = localStorage.getItem(cacheKey);
+		const cachedVersion = localStorage.getItem(cacheVersionKey);
 
-		if (cachedTime && cachedVoices) {
+		// Check if cache is valid (not expired AND correct version)
+		if (cachedTime && cachedVoices && cachedVersion === currentVersion) {
 			const age = Date.now() - parseInt(cachedTime, 10);
 			if (age < cacheExpiration) {
-				console.log('Using cached voices data');
+				console.log('Using cached voices data (v' + currentVersion + ')');
 				const voices = JSON.parse(cachedVoices);
 				renderVoiceOptions(voiceSelection, voices);
 				return voices;
 			}
+		} else if (cachedVersion !== currentVersion) {
+			console.log('Cache version mismatch - invalidating old cache');
+			// Clear old cache
+			localStorage.removeItem(cacheKey);
+			localStorage.removeItem(cacheTimeKey);
+			localStorage.removeItem(cacheVersionKey);
 		}
 	} catch (error) {
 		console.warn('Cache read failed:', error);
@@ -39,10 +49,11 @@ async function populateVoiceDropdown(voiceSelection) {
 
 		const data = await response.json();
 
-		// Cache the response
+		// Cache the response with version
 		try {
 			localStorage.setItem(cacheKey, JSON.stringify(data.voices));
 			localStorage.setItem(cacheTimeKey, Date.now().toString());
+			localStorage.setItem(cacheVersionKey, currentVersion);
 		} catch (error) {
 			console.warn('Cache write failed:', error);
 		}