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/resources/index.ts

@@ -0,0 +1,22 @@
+import type { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js'
+import type { SceneBridge } from '../bridge/scene-bridge'
+import { registerCatalogItems } from './catalog-items'
+import { registerConstraints } from './constraints'
+import { registerSceneCurrent } from './scene-current'
+import { registerSceneSummary } from './scene-summary'
+
+/**
+ * Registers all MCP resources exposed by `@pascal-app/mcp`.
+ *
+ * Resources:
+ * - `pascal://scene/current`          — application/json, full snapshot
+ * - `pascal://scene/current/summary`  — text/markdown, human summary
+ * - `pascal://catalog/items`          — application/json, host-supplied catalog
+ * - `pascal://constraints/{levelId}`  — application/json, per-level constraints
+ */
+export function registerResources(server: McpServer, bridge: SceneBridge): void {
+  registerSceneCurrent(server, bridge)
+  registerSceneSummary(server, bridge)
+  registerCatalogItems(server, bridge)
+  registerConstraints(server, bridge)
+}