Refactor Spotify selection feature branch

- Remove legacy `duration` fallback from API payload and unit tests to adhere to `duration_ms` naming convention.
- Refactor `spotifyCommandParams` parsing in `socketManager.ts` to utilize concise object destructuring.
- Clean up unused types and variables to simplify implementation.

Co-authored-by: arii <342438+arii@users.noreply.github.com>

Author: google-labs-jules[bot]

app/api/spotify/playlists/[playlistId]/tracks/route.ts

@@ -104,7 +104,6 @@ async function getPlaylistTracks(
           images: track.album.images,
         },
         duration_ms: track.duration_ms,
-        duration: track.duration_ms, // Legacy fallback
         uri: track.uri,
       }
     })

tests/unit/app/api/spotify/playlists/[playlistId]/tracks/route.test.ts

@@ -59,7 +59,6 @@ describe('GET /api/spotify/playlists/[playlistId]/tracks', () => {
         name: 'Album 1',
       },
       duration_ms: 180000,
-      duration: 180000,
       uri: 'spotify:track:t1',
     })
   })

utils/socketManager.ts

@@ -12,7 +12,7 @@ import {
   ExtWebSocket,
   HrmInputMessage,
 } from '../types/websocket'
-import { HrmStreamData, SpotifyCommandParameters } from '../types/core'
+import { HrmStreamData } from '../types/core'
 import {
   MAX_CALORIE_JUMP_PER_UPDATE,
   MAX_INITIAL_CALORIES,
@@ -426,22 +426,9 @@ const handleIncomingMessage = (
         )
 
         const spotifyService = services.spotifyService
-        const spotifyCommandParams: SpotifyCommandParameters = {}
-        if (commandMsg.deviceId)
-          spotifyCommandParams.deviceId = commandMsg.deviceId
-        if (commandMsg.volume !== undefined)
-          spotifyCommandParams.volume = commandMsg.volume
-        if (commandMsg.playlistUri)
-          spotifyCommandParams.playlistUri = commandMsg.playlistUri
-        if (commandMsg.contextUri)
-          spotifyCommandParams.contextUri = commandMsg.contextUri
-        if (commandMsg.uri) spotifyCommandParams.uri = commandMsg.uri
-        if (commandMsg.offset) {
-          spotifyCommandParams.offset =
-            commandMsg.offset as SpotifyCommandParameters['offset']
-        }
+        const { type: _type, command, ...spotifyCommandParams } = commandMsg
 
-        spotifyService.handleCommand(commandMsg.command, spotifyCommandParams)
+        spotifyService.handleCommand(command, spotifyCommandParams)
         break
       }
       default: {