feat(transcoding): add FFmpeg HLS transcoding support

- Introduced `TranscodeManager` for managing on-demand transcoding of local video files.
- Added configuration options for transcoding in `Config` and `LocalFilesConfig`.
- Implemented new API routes for managing transcoding settings, stats, and cache.
- Updated `LocalFilesProvider` to support transcoding capabilities.
- Created frontend components for managing transcode settings and displaying stats.
- Added database migration for transcode settings.
- Enhanced existing routes and DTOs to accommodate new transcoding features.

k-tv-backend/api/Cargo.toml

@@ -11,7 +11,7 @@ postgres = ["infra/postgres"]
 auth-oidc = ["infra/auth-oidc"]
 auth-jwt = ["infra/auth-jwt"]
 jellyfin = ["infra/jellyfin"]
-local-files = ["infra/local-files", "dep:tokio-util"]
+local-files = ["infra/local-files", "dep:tokio-util", "dep:sqlx"]
 
 [profile.release]
 strip = true
@@ -61,3 +61,4 @@ async-trait = "0.1"
 dotenvy = "0.15.7"
 time = "0.3"
 tokio-util = { version = "0.7", features = ["io"], optional = true }
+sqlx = { version = "0.8.6", features = ["runtime-tokio", "sqlite"], optional = true }