Initial house specification: air system, sensors, Lindner Doppelboden + Plafotherm ceiling

- 01: H13 HEPA whole-house air filtration, MVHR, duct design, pressure management
- 02: Sensor placement, automation logic, Home Assistant integration, wiring
- 03: Baufritz builder coordination, construction checkpoints, timeline
- 04: Lindner NORTEC Doppelboden with WOODline parquet + Plafotherm AirHybrid radiant ceiling
- Build system: tsx + marked + puppeteer, renders Mermaid diagrams to PDF

package.json

@@ -0,0 +1,22 @@
+{
+  "name": "@maintainable.xyz/house-spec",
+  "version": "1.0.0",
+  "private": true,
+  "description": "Baufritz house specification \u2014 air system, sensors, and builder coordination",
+  "type": "module",
+  "scripts": {
+    "build": "tsx build.ts"
+  },
+  "devDependencies": {
+    "tsx": "^4.19.0",
+    "marked": "^15.0.0",
+    "puppeteer": "^24.0.0",
+    "@types/node": "^22.0.0"
+  },
+  "pnpm": {
+    "onlyBuiltDependencies": [
+      "esbuild",
+      "puppeteer"
+    ]
+  }
+}