feat(mcp): add resources and prompts

Resources: pascal://scene/current (JSON), /scene/current/summary
(markdown with per-level counts, floor areas, bbox), /catalog/items
(returns catalog_unavailable in headless mode), and the templated
pascal://constraints/{levelId} which exposes slabs + wall footprints
via @pascal-app/core/wall helpers.

Prompts: from_brief (generate scene from a natural-language brief),
iterate_on_feedback (minimal-diff patch proposals), and
renovation_from_photos (orchestrates the vision tools).

17 tests, all passing.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/mcp/src/prompts/index.ts

@@ -0,0 +1,17 @@
+import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'
+import type { SceneBridge } from '../bridge/scene-bridge'
+import { registerFromBrief } from './from-brief'
+import { registerIterateOnFeedback } from './iterate-on-feedback'
+import { registerRenovationFromPhotos } from './renovation-from-photos'
+
+/**
+ * Registers all MCP prompts exposed by `@pascal-app/mcp`:
+ * - `from_brief`                — generate a scene from a natural-language brief
+ * - `iterate_on_feedback`       — minimal-diff patches from user feedback
+ * - `renovation_from_photos`    — photo-driven renovation plan via vision tools
+ */
+export function registerPrompts(server: McpServer, bridge: SceneBridge): void {
+  registerFromBrief(server, bridge)
+  registerIterateOnFeedback(server, bridge)
+  registerRenovationFromPhotos(server, bridge)
+}