Implement Spawn view

[2witstudios]

Epic 6: iOS App — State & Views — Issue 4/5

Source: 1-agent worktree — most feature-complete spawn form

Description

Form for spawning new worktrees with agents from the iOS app.

Acceptance Criteria

• SpawnView.swift — form with:
  • Name field (required)
  • Prompt TextEditor (multi-line)
  • Agent type picker (claude/codex/opencode)
  • Count stepper (1-10)
  • Base branch picker
  • Quick prompt templates section
• Form validation (name required, prompt or template required)
• Loading state during spawn
• Clear form on success
• Navigate to new worktree detail on completion

Dependencies

• Requires: Implement REST client (PPGClient) #78 (PPGClient), Implement iOS state management (AppState + ManifestStore) #82 (AppState)

Files to Create

• ios/PPGMobile/PPGMobile/Views/Spawn/SpawnView.swift (new)