feat(api): media detail + info + image-folder endpoints (#141/#161)

Add REST endpoints backing the SPA media detail pages and image browser:

- GET /api/movies/{id}, /api/shows/{id}, /api/seasons/{id}, /api/artists/{id}
  wrapping the existing detail queries; 404 on None.
- GET /api/media-items/{id}/info wrapping GetMediaItemInfo; UnableToLocateMediaItem
  -> 404, other errors -> 422.
- GET /api/images/folders?parentId= and PUT /api/images/folders/{id}/duration
  (validates null-or-positive -> 400; existence guard via new ImageFolderExists
  query -> 404).
- Extend GetLibraryBrowseItems parentId drill-in to Episode (episodes of a season,
  episode-number order) and MusicVideo (an artist's music videos, album/track order),
  alongside the existing TelevisionSeason branch.

Response DTOs live in ErsatzTV.Core/Api/* and never expose Application VMs. Artwork
values are rooted for the SPA via a shared ErsatzTV.Core/Api/ApiArtwork helper
(mirrors the #180/#181 browse-handler logic; handles jellyfin/emby proxy prefixes,
http passthrough, empty). Regenerated OpenAPI v1.json + web v1.d.ts. New controllers
registered in ApiControllerSecurityTests.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

web/src/api/generated/v1.d.ts

@@ -3,6 +3,12 @@
 
 export interface components {
   schemas: {
+    "ActorResponseModel": {
+    "id": number;
+    "name": string;
+    "role": null | string;
+    "thumb": string;
+  };
     "AddItemsToCollectionRequest": {
     "movieIds": null | Array<number>;
     "showIds": null | Array<number>;
@@ -17,6 +23,18 @@ export interface components {
   };
     "AddTraktListRequest": {
     "url": null | string;
+  };
+    "ArtistDetailResponseModel": {
+    "id": number;
+    "name": string;
+    "disambiguation": null | string;
+    "biography": null | string;
+    "thumbnail": string;
+    "fanArt": string;
+    "genres": Array<string>;
+    "styles": Array<string>;
+    "moods": Array<string>;
+    "languages": Array<string>;
   };
     "ArtworkContentTypeModel": {
     "path": null | string;
@@ -687,6 +705,14 @@ export interface components {
     "lastAccess": string;
   };
     "IFormFile": string;
+    "ImageFolderResponseModel": {
+    "libraryFolderId": number;
+    "name": string;
+    "fullPath": string;
+    "subfolderCount": number;
+    "imageCount": number;
+    "durationSeconds": null | number;
+  };
     "LibraryBrowseItemResponseModel": {
     "id": number;
     "mediaType": components["schemas"]["LibraryBrowseMediaType"];
@@ -739,8 +765,54 @@ export interface components {
     "poster"?: null | string;
     "state": components["schemas"]["MediaItemState"];
     "hasMediaInfo"?: boolean;
+  };
+    "MediaItemInfoChapterResponseModel": {
+    "title": null | string;
+    "startTime": string;
+    "endTime": string;
+  };
+    "MediaItemInfoResponseModel": {
+    "id": number;
+    "title": string;
+    "kind": string;
+    "libraryKind": string;
+    "serverName": null | string;
+    "libraryName": string;
+    "state": components["schemas"]["MediaItemState"];
+    "duration": string;
+    "sampleAspectRatio": null | string;
+    "displayAspectRatio": null | string;
+    "rFrameRate": null | string;
+    "videoScanKind": components["schemas"]["VideoScanKind"];
+    "interlacedRatio": null | number;
+    "width": number;
+    "height": number;
+    "streams": Array<components["schemas"]["MediaItemInfoStreamResponseModel"]>;
+    "chapters": Array<components["schemas"]["MediaItemInfoChapterResponseModel"]>;
+  };
+    "MediaItemInfoStreamResponseModel": {
+    "index": null | number;
+    "kind": components["schemas"]["MediaStreamKind"];
+    "title": null | string;
+    "codec": null | string;
+    "profile": null | string;
+    "language": null | string;
+    "channels": null | number;
+    "default": null | boolean;
+    "forced": null | boolean;
+    "attachedPic": null | boolean;
+    "pixelFormat": null | string;
+    "colorRange": null | string;
+    "colorSpace": null | string;
+    "colorTransfer": null | string;
+    "colorPrimaries": null | string;
+    "bitsPerRawSample": null | number;
+    "mimeType": null | string;
+    "fileName": null | string;
+    "isExtracted": null | boolean;
   };
     "MediaItemState": "Normal" | "FileNotFound" | "Unavailable" | "RemoteOnly";
+    "MediaSourceKind": "Local" | "Plex" | "Jellyfin" | "Emby";
     "MediaSourceLibraryResponseModel": {
     "id": number;
     "name": string;
@@ -754,6 +826,26 @@ export interface components {
     "name": string;
     "connectionAddress": null | string;
     "libraries": Array<components["schemas"]["MediaSourceLibraryResponseModel"]>;
+  };
+    "MediaStreamKind": "Video" | "Audio" | "Subtitle" | "Attachment" | "ExternalSubtitle";
+    "MovieDetailResponseModel": {
+    "id": number;
+    "title": string;
+    "year": null | string;
+    "plot": null | string;
+    "genres": Array<string>;
+    "tags": Array<string>;
+    "studios": Array<string>;
+    "contentRatings": Array<string>;
+    "languages": Array<string>;
+    "actors": Array<components["schemas"]["ActorResponseModel"]>;
+    "directors": Array<string>;
+    "writers": Array<string>;
+    "path": null | string;
+    "localPath": null | string;
+    "state": components["schemas"]["MediaItemState"];
+    "poster": string;
+    "fanArt": string;
   };
     "MultiCollectionItemViewModel": {
     "multiCollectionId": number;
@@ -1121,6 +1213,32 @@ export interface components {
     "otherVideos": components["schemas"]["SearchResultGroupResponseModel"];
     "images": components["schemas"]["SearchResultGroupResponseModel"];
     "remoteStreams": components["schemas"]["SearchResultGroupResponseModel"];
+  };
+    "SeasonDetailResponseModel": {
+    "id": number;
+    "showId": number;
+    "title": string;
+    "year": null | string;
+    "name": string;
+    "poster": string;
+    "fanArt": string;
+  };
+    "ShowDetailResponseModel": {
+    "id": number;
+    "libraryId": number;
+    "mediaSourceKind": components["schemas"]["MediaSourceKind"];
+    "title": string;
+    "year": null | string;
+    "plot": null | string;
+    "poster": string;
+    "fanArt": string;
+    "genres": Array<string>;
+    "tags": Array<string>;
+    "studios": Array<string>;
+    "networks": Array<string>;
+    "contentRatings": Array<string>;
+    "languages": Array<string>;
+    "actors": Array<components["schemas"]["ActorResponseModel"]>;
   };
     "SmartCollectionResponseModel": {
     "id": number;
@@ -1318,6 +1436,12 @@ export interface components {
   };
     "UpdateHdhrSettingsRequest": {
     "tunerCount": number;
+  };
+    "UpdateImageFolderDurationRequest": {
+    "durationSeconds": null | number;
+  };
+    "UpdateImageFolderDurationResponseModel": {
+    "durationSeconds": null | number;
   };
     "UpdateLoggingSettingsRequest": {
     "defaultMinimumLogLevel": components["schemas"]["LogEventLevel"];
@@ -1383,6 +1507,7 @@ export interface components {
     "blockBehavior": components["schemas"]["XmltvBlockBehavior"];
   };
     "VaapiDriver": "Default" | "iHD" | "i965" | "RadeonSI" | "Nouveau";
+    "VideoScanKind": "Unknown" | "Progressive" | "Interlaced";
     "WatermarkFullResponseModel": {
     "id": number;
     "name": string;