[qrrk]

Changes

• Settings: Added check_external_stable_release_source (default true) and configurable external_stable_release_source endpoint in default_settings.json.
• Automatic Checking & Caching: On startup, checks the configured source (URL or local filesystem path) in the background without blocking the UI. Caches discovered releases to release_info_cache.json in the launcher directory for instant offline availability.
• Smart Merging: Performs union merge (external -> cache -> res://data/stable_releases.json) preserving chronological ordering and built-in fallback releases without duplicates.
• Settings UI: Added "Check online for new stable game releases" switch in the Settings tab, and enabled manual refresh button on the stable channel when the setting is active.
• Translations: Added localized strings and wrapped tooltips across all 10 supported languages.