Improve UX

[Gawor270]

• Added two-step game selection flow, first users select story which is upadated on the backend and then they can start a game with selected story
• Added new backend endpoints selectStory and stopGame to support the two-step workflow
• Updated UI to show conditional buttons based on game state (Choose Story → Start Game/Cancel)
• Make starting another game possible after ending current one
• Display message when user tries to enter empty username
• Fix invisible items in device selection list

[Copilot]

Pull Request Overview

This PR separates story selection from game starting into a two-step workflow. Players now select a scenario first, then explicitly start the game, with the ability to cancel an active game.

• Refactored story selection to emit a storySelected event without immediately starting the game
• Added new backend endpoints selectStory and stopGame to support the two-step workflow
• Updated UI to show conditional buttons based on game state (Choose Story → Start Game/Cancel)

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
deep-sea-stories/packages/web/src/views/GameView.tsx	Extracted userName from localPeer metadata and passed it to RoomControls
deep-sea-stories/packages/web/src/components/StorySelectionPanel.tsx	Changed to call selectStory mutation instead of startStory, removed DialogDescription import, updated button and toast messaging
deep-sea-stories/packages/web/src/components/RoomControls.tsx	Added state management for story selection and game lifecycle, implemented handlers for starting and cancelling games, conditional UI based on game state
deep-sea-stories/packages/web/src/components/AgentPanel.tsx	Added rendering for storySelected events, removed agent visualizer image display, removed unused import
deep-sea-stories/packages/common/src/events.ts	Added StorySelectedEvent type to the events union
deep-sea-stories/packages/backend/src/schemas.ts	Split startStoryInputSchema into selectStoryInputSchema and startStoryInputSchema, added stopGameInputSchema
deep-sea-stories/packages/backend/src/router.ts	Added selectStory and stopGame endpoints to the router
deep-sea-stories/packages/backend/src/controllers/stories.ts	Refactored startStory into selectStory (sets story without starting) and startStory (starts previously selected story), added stopGame handler

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[czerwiukk]

one nit, lgtm