Bug and crash fixes (#132)

* feat(EPUB): adapt status bar icon visibility to reader theme

Pass the reader's active isDarkTheme state to EpubReaderSystemUiController to ensure status bar icons automatically switch between light and dark to remain visible against the selected background/page color.

* Implement storage tracking and optimize cache management

This commit introduces a `StorageTracker` to monitor disk usage and implements several optimizations to prevent cache bloat and handle orphaned files.

* refactor: unify book extraction paths and fix cache leaks

- Replaced random UUID and title-based hashing with stable `bookId` for extraction directories across Epub, Mobi, and FB2 parsers.
- Standardized all temporary extraction paths to `cache/imported_file_${bookId}`.
- Updated MainViewModel and MetadataExtractionWorker to provide the mandatory `bookId` during parsing.
- Ensured `clearImportedFileCache` successfully targets the correct directories on book deletion.
- Added a legacy cleanup task in `sweepOrphanedCache` to reclaim storage from old `extracted_epubs` folders.

* fix(pdf): handle NoClassDefFoundError for PdfPasswordException

Updated the PDF loading logic in PdfViewerScreen to catch Throwable
instead of Exception. This prevents the app from crashing when the
underlying pdfium library attempts to throw a PdfPasswordException
that is missing from the runtime classpath (NoClassDefFoundError).

* fix(tts): set language before voice to prevent variant reset

* EpubReaderScreen: increase scroll-hide ignore duration for tap toggles

Increase the threshold for ignoring tap toggles after bars are hidden by scrolling from 250ms to 400ms. This prevents accidental UI toggles caused by "sloppy taps" immediately following a scroll action.

* fix: resolve large bitmap crash on tall PDF pages

- Caps base layer bitmap dimensions to 3000px to prevent GPU texture limit crashes.
- Enables tiled rendering for large pages even at 1x zoom to maintain sharpness.
- Optimizes PdfBitmapPool to support rectangular bitmap allocations.

* Common.kt: ensure unique keys in voice list

* fix: handle ActivityNotFoundException in folder sync screen

* Improve file deletion logic and fix chapter index bounds in epub reader

* fix: ensure WebView bridge callbacks run on UI thread

This resolves a WebViewMethodCalledOnWrongThreadViolation in vertical mode that was preventing chapter chunks from loading beyond the initial viewport.

app/src/main/java/com/aryan/reader/tts/BaseTtsSynthesizer.kt

@@ -154,12 +154,12 @@ class BaseTtsSynthesizer(private val context: Context) {
                 val targetVoice = availableVoices.find { it.name == preferredVoiceName }
                 if (targetVoice != null) {
                     Timber.d("BaseTts: Setting preferred voice to ${targetVoice.name} (${targetVoice.locale})")
-                    tts?.voice = targetVoice
                     try {
                         tts?.language = targetVoice.locale
                     } catch (e: Exception) {
                         Timber.e(e, "BaseTts: Failed to set language for voice")
                     }
+                    tts?.voice = targetVoice
                 } else {
                     Timber.w("BaseTts: Preferred voice '$preferredVoiceName' not found in current engine.")
                 }