[FEATURE]: Add DELETE /project/:id endpoint to remove stale projects #25004

Problem

OpenCode has CRUD for sessions but only CRU for projects:

• GET /project — list
• GET /project/current — get current
• PATCH /project/:id — update
• DELETE — missing

This causes:

1. Stale project entries that cannot be removed — users report in:

   • Title: (OpenCode-Desktop) Open Project no longer detects manually created git worktrees as workspaces, and stale workspace entries cannot be removed on macOS #21554 — stale workspace entries cannot be removed on macOS
   • [FEATURE]:good way to manage stored data #8083 — "a good way to clear everything or categorize then delete a project would be super helpful"

2. No API-driven cleanup — users resort to manual SQLite manipulation or community tools like opencode-project-manager

3. Blocks downstream features — Telegram bots, workspace management, and storage reclamation ([FEATURE]: Session Lifecycle Management — unified storage reclamation, auto-archival, and child session cleanup #16101) cannot programmatically remove projects

4. Orphaned sessions — Sessions become orphaned when project directory is renamed #23248 shows sessions become invisible when directories are renamed/moved; [FEATURE]: Add session migration dialog to recover orphaned or misplaced sessions #23249 proposes migration, but deleting the dead project is often the simpler fix

Proposal

Add DELETE /project/:projectID:

• Deletes the project row from the project table
• Foreign key cascade (ON DELETE CASCADE) automatically removes all associated sessions, messages, parts, todos, and permissions
• Response: { deleted: true, sessionsRemoved: <count> }
• Returns 404 for non-existent project IDs

Scope

• Project.remove(id) — Effect service method
• DELETE /project/:projectID — Hono route (server)
• DELETE /project/:projectID — HttpApi endpoint (for SDK generation)
• SDK client regenerates from OpenAPI annotations automatically
• No TUI/Desktop UI changes in this PR

Related

• Title: (OpenCode-Desktop) Open Project no longer detects manually created git worktrees as workspaces, and stale workspace entries cannot be removed on macOS #21554 — stale workspace entries cannot be removed
• [FEATURE]:good way to manage stored data #8083 — good way to manage stored data
• [FEATURE]: Session Lifecycle Management — unified storage reclamation, auto-archival, and child session cleanup #16101 — Session Lifecycle Management
• Sessions become orphaned when project directory is renamed #23248 — Sessions become orphaned when project directory is renamed
• [FEATURE]: Add session migration dialog to recover orphaned or misplaced sessions #23249 — Session migration dialog for orphaned sessions