feat: implement multi-provider support in media library

- Introduced IProviderRegistry to manage multiple media providers.
- Updated AppState to use provider_registry instead of a single media_provider.
- Refactored library routes to support provider-specific queries for collections, series, genres, and items.
- Enhanced ProgrammingBlock to include provider_id for algorithmic and manual content types.
- Modified frontend components to allow selection of providers and updated API calls to include provider parameters.
- Adjusted hooks and types to accommodate provider-specific functionality.

k-tv-backend/domain/src/entities.rs

@@ -214,7 +214,7 @@ impl ProgrammingBlock {
             name: name.into(),
             start_time,
             duration_mins,
-            content: BlockContent::Algorithmic { filter, strategy },
+            content: BlockContent::Algorithmic { filter, strategy, provider_id: String::new() },
             loop_on_finish: true,
             ignore_recycle_policy: false,
             access_mode: AccessMode::default(),
@@ -233,7 +233,7 @@ impl ProgrammingBlock {
             name: name.into(),
             start_time,
             duration_mins,
-            content: BlockContent::Manual { items },
+            content: BlockContent::Manual { items, provider_id: String::new() },
             loop_on_finish: true,
             ignore_recycle_policy: false,
             access_mode: AccessMode::default(),
@@ -247,11 +247,21 @@ impl ProgrammingBlock {
 #[serde(tag = "type", rename_all = "snake_case")]
 pub enum BlockContent {
     /// The user hand-picked specific items in a specific order.
-    Manual { items: Vec<MediaItemId> },
+    /// Item IDs are prefixed with the provider key (e.g. `"jellyfin::abc123"`)
+    /// so the registry can route each fetch to the correct provider.
+    Manual {
+        items: Vec<MediaItemId>,
+        /// Registry key of the provider these items come from. Empty string = primary.
+        #[serde(default)]
+        provider_id: String,
+    },
     /// The engine selects items from the provider using the given filter and strategy.
     Algorithmic {
         filter: MediaFilter,
         strategy: FillStrategy,
+        /// Registry key of the provider to query. Empty string = primary.
+        #[serde(default)]
+        provider_id: String,
     },
 }