refactor: migrate JS/MJS sources and scripts to TypeScript

Migrate all remaining migratable .js/.mjs files to .ts with strong typing:
- constants/MediaTypes: as const + derived MediaType union
- utils/profiles/{download,subtitles,trackplayer}: typed against
  @jellyfin/sdk DeviceProfile/SubtitleProfile/CodecProfile models;
  native.ts now validates its profile with `satisfies DeviceProfile`
- trackplayer.d.ts removed (superseded by real TS implementation)
- index.js -> index.ts (entry point, "main" is extension-less)
- scripts/{typecheck,check-i18n-keys,detect-duplicate-issue} -> .ts,
  all run via bun (typecheck switched from node to bun)

Remove scripts/symlink-native-dirs.js: dead since 446439c2 (2025-02-28)
when its only reference (prebuild:tv-new) was dropped; superseded by
`expo prebuild --clean` + cross-env EXPO_TV. Drop the matching
.gitignore relics (/iostv, /iosmobile, /androidmobile, /androidtv).

Document tooling-required .js exceptions (babel/metro/react-native/
tailwind configs) in CLAUDE.md and copilot-instructions.md so code
review guidelines stop flagging them.

utils/profiles/download.ts

@@ -3,17 +3,17 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
-import { generateDeviceProfile } from "./native";
-
-/**
- * @typedef {"auto" | "stereo" | "5.1" | "passthrough"} AudioTranscodeModeType
- */
+import type {
+  DeviceProfile,
+  SubtitleProfile,
+} from "@jellyfin/sdk/lib/generated-client/models";
+import { type AudioTranscodeModeType, generateDeviceProfile } from "./native";
 
 /**
  * Download-specific subtitle profiles.
  * These are more permissive than streaming profiles since we can embed subtitles.
  */
-const downloadSubtitleProfiles = [
+const downloadSubtitleProfiles: SubtitleProfile[] = [
   // Official formats
   { Format: "vtt", Method: "Encode" },
   { Format: "webvtt", Method: "Encode" },
@@ -46,11 +46,10 @@ const downloadSubtitleProfiles = [
 /**
  * Generates a device profile optimized for downloads.
  * Uses the same audio codec logic as streaming but with download-specific bitrate limits.
- *
- * @param {AudioTranscodeModeType} [audioMode="auto"] - Audio transcoding mode
- * @returns {Object} Jellyfin device profile for downloads
  */
-export const generateDownloadProfile = (audioMode = "auto") => {
+export const generateDownloadProfile = (
+  audioMode: AudioTranscodeModeType = "auto",
+): DeviceProfile => {
   // Get the base profile with proper audio codec configuration
   const baseProfile = generateDeviceProfile({ audioMode });
 

utils/profiles/native.ts

@@ -3,6 +3,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
+import type { DeviceProfile } from "@jellyfin/sdk/lib/generated-client/models";
 import { Platform } from "react-native";
 import MediaTypes from "../../constants/MediaTypes";
 import { getSubtitleProfiles } from "./subtitles";
@@ -193,7 +194,7 @@ export const generateDeviceProfile = (options: ProfileOptions = {}) => {
       },
     ],
     SubtitleProfiles: getSubtitleProfiles(),
-  };
+  } satisfies DeviceProfile;
 
   return profile;
 };

utils/profiles/subtitles.ts

@@ -3,6 +3,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
+import type { SubtitleProfile } from "@jellyfin/sdk/lib/generated-client/models";
 
 // Image-based formats - these need to be burned in by Jellyfin (Encode method)
 // because MPV cannot load them externally over HTTP
@@ -13,7 +14,7 @@ const IMAGE_BASED_FORMATS = [
   "pgssub",
   "teletext",
   "vobsub",
-];
+] as const;
 
 // Text-based formats - these can be loaded externally by MPV
 const TEXT_BASED_FORMATS = [
@@ -37,10 +38,10 @@ const TEXT_BASED_FORMATS = [
   "text",
   "vplayer",
   "xsub",
-];
+] as const;
 
-export const getSubtitleProfiles = () => {
-  const profiles = [];
+export const getSubtitleProfiles = (): SubtitleProfile[] => {
+  const profiles: SubtitleProfile[] = [];
 
   // Image-based formats: Embed or Encode (burn-in), NOT External
   for (const format of IMAGE_BASED_FORMATS) {
@@ -58,4 +59,4 @@ export const getSubtitleProfiles = () => {
 };
 
 // Export for use in player filtering
-export const IMAGE_SUBTITLE_CODECS = IMAGE_BASED_FORMATS;
+export const IMAGE_SUBTITLE_CODECS: readonly string[] = IMAGE_BASED_FORMATS;

utils/profiles/trackplayer.d.ts

@@ -1,19 +0,0 @@
-/**
- * This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/.
- */
-
-export type PlatformType = "ios" | "android";
-
-export interface TrackPlayerProfileOptions {
-  /** Target platform */
-  platform?: PlatformType;
-}
-
-export function generateTrackPlayerProfile(
-  options?: TrackPlayerProfileOptions,
-): any;
-
-declare const _default: any;
-export default _default;

utils/profiles/trackplayer.ts

@@ -3,23 +3,26 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
  */
+import type {
+  CodecProfile,
+  DeviceProfile,
+  DirectPlayProfile,
+} from "@jellyfin/sdk/lib/generated-client/models";
 import { Platform } from "react-native";
 import MediaTypes from "../../constants/MediaTypes";
 
-/**
- * @typedef {"ios" | "android"} PlatformType
- *
- * @typedef {Object} TrackPlayerProfileOptions
- * @property {PlatformType} [platform] - Target platform
- */
+export type PlatformType = "ios" | "android";
+
+export interface TrackPlayerProfileOptions {
+  /** Target platform */
+  platform?: PlatformType;
+}
 
 /**
  * Audio direct play profiles for react-native-track-player.
  * iOS uses AVPlayer, Android uses ExoPlayer - each has different codec support.
- *
- * @param {PlatformType} platform
  */
-const getDirectPlayProfile = (platform) => {
+const getDirectPlayProfile = (platform: PlatformType): DirectPlayProfile => {
   if (platform === "ios") {
     // iOS AVPlayer supported formats
     return {
@@ -39,10 +42,8 @@ const getDirectPlayProfile = (platform) => {
 
 /**
  * Audio codec profiles for react-native-track-player.
- *
- * @param {PlatformType} platform
  */
-const getCodecProfile = (platform) => {
+const getCodecProfile = (platform: PlatformType): CodecProfile => {
   if (platform === "ios") {
     // iOS AVPlayer codec constraints
     return {
@@ -64,12 +65,11 @@ const getCodecProfile = (platform) => {
  * This profile is specifically for standalone audio playback using:
  * - AVPlayer on iOS
  * - ExoPlayer on Android
- *
- * @param {TrackPlayerProfileOptions} [options] - Profile configuration options
- * @returns {Object} Jellyfin device profile for track player
  */
-export const generateTrackPlayerProfile = (options = {}) => {
-  const platform = options.platform || Platform.OS;
+export const generateTrackPlayerProfile = (
+  options: TrackPlayerProfileOptions = {},
+): DeviceProfile => {
+  const platform = (options.platform || Platform.OS) as PlatformType;
 
   return {
     Name: "Track Player",