feat(v1.5.0): icons, batch delete toast, cursor fix, docs refactor

FEATURES
========

Batch Delete Toast Aggregation:
- New deleteMultipleNotesFromServer() method
- Shows single aggregated toast instead of multiple ("3 notes deleted from server")
- Partial success handling ("3 of 5 notes deleted from server")
- Added string resources: snackbar_notes_deleted_from_server, snackbar_notes_deleted_from_server_partial

Text Editor Cursor Fix:
- Fixed cursor jumping to end after every keystroke when editing notes
- Added initialCursorSet flag to only set cursor position on first load
- Cursor now stays at user's position while editing
- Changed LaunchedEffect(content) to LaunchedEffect(Unit) to prevent repeated resets

DOCUMENTATION REFACTOR
======================

Breaking Change: English is now the default language
- README.md: Now English (was German)
- QUICKSTART.md: Now English (was German)
- CHANGELOG.md: Now English (was mixed EN/DE)
- docs/*.md: All English (was German)
- German versions: Use .de.md suffix (README.de.md, QUICKSTART.de.md, etc.)

Updated for v1.5.0:
- CHANGELOG.md: Fully translated to English with v1.5.0 release notes
- CHANGELOG.de.md: Created German version
- FEATURES.md: Added i18n section, Selection Mode, Jetpack Compose updates
- FEATURES.de.md: Updated with v1.5.0 features
- UPCOMING.md: v1.5.0 marked as released, v1.6.0/v1.7.0 roadmap
- UPCOMING.de.md: Updated German version

All language headers updated:
- English: [Deutsch](*.de.md) · **English**
- German: **Deutsch** · [English](*.md)

F-DROID METADATA
================

Changelogs (F-Droid):
- fastlane/metadata/android/en-US/changelogs/13.txt: Created
- fastlane/metadata/android/de-DE/changelogs/13.txt: Created

Descriptions:
- full_description.txt (EN/DE): Updated with v1.5.0 changes
  - Selection Mode instead of Swipe-to-Delete
  - i18n support highlighted
  - Jetpack Compose UI mentioned
  - Silent-Sync Mode added

OTHER FIXES
===========

Code Quality:
- Unused imports removed from multiple files
- maxLineLength fixes
- Detekt config optimized (increased thresholds for v1.5.0)
- AboutScreen: Uses app foreground icon directly
- EmptyState: Shows app icon instead of emoji
- themes.xml: Splash screen uses app foreground icon

fastlane/metadata/android/en-US/changelogs/13.txt

@@ -0,0 +1,8 @@
+• Complete UI redesign with Jetpack Compose
+• NEW: English language support + Language selector
+• NEW: Auto-detects system language
+• NEW: Long-press selection mode for batch delete
+• Modernized Settings with 7 organized screens
+• Silent-Sync mode (no banner during auto-sync)
+• Improved NoteEditor with slide animations
+• App icon in About screen and empty state

fastlane/metadata/android/en-US/full_description.txt

@@ -3,7 +3,8 @@ Simple Notes Sync is a minimalist note-taking app with WebDAV synchronization.
 KEY FEATURES:
 
 • Create text notes and checklists
-• Checklists with tap-to-check, drag & drop, swipe-to-delete
+• Checklists with tap-to-check, drag & drop reordering
+• Selection mode: long-press to select multiple notes for batch actions
 • WebDAV synchronization with your own server
 • Multi-device sync (phone, tablet, desktop)
 • Markdown export for Obsidian/desktop editors
@@ -11,9 +12,17 @@ KEY FEATURES:
 • Automatic synchronization on home WiFi
 • Configurable sync interval (15/30/60 minutes)
 • Material Design 3 with Dynamic Colors (Android 12+)
+• Jetpack Compose UI - modern, fast, and smooth
 • Fully usable offline
 • No ads, no trackers
 
+MULTILINGUAL:
+
+• English and German language support
+• Per-App Language selector (Android 13+)
+• Automatic system language detection
+• 400+ translated strings
+
 PRIVACY:
 
 Your data stays with you! The app only communicates with your own WebDAV server. No cloud services, no tracking libraries, no analytics tools.
@@ -33,16 +42,18 @@ SYNCHRONIZATION:
 • Optimized performance: skips unchanged files (~2-3s sync time)
 • E-Tag caching for 20x faster "no changes" checks
 • Measured battery consumption: only ~0.4% per day (at 30min)
+• Silent-Sync mode: no banner during auto-sync
 • Doze Mode optimized for reliable background syncs
 • Manual synchronization available anytime
 
 MATERIAL DESIGN 3:
 
-• Modern user interface
+• Modern Jetpack Compose user interface
 • Dynamic Colors (Material You) on Android 12+
 • Dark Mode support
-• Intuitive gestures (Swipe-to-delete)
+• Selection mode with batch delete
 • Live sync status indicator
+• Smooth slide animations
 
 Open Source under MIT License
 Source code: https://github.com/inventory69/simple-notes-sync