PR-001: Domain Model v1.0 — compile-only, zero dependencies

- @landvex/domain package with TypeScript strict mode
- 3 Aggregate Roots: FieldSession, Mission, DecisionCase
- Branded IDs, Value Objects, Domain Events, Invariants
- 19 unit tests for IDs, FieldSession, DecisionCase
- Zero runtime dependencies (only TypeScript + jest for tests)
- Separates Entity / Value Object / Aggregate Root
- README documents Three Rules of the domain

Definition of Done met:
- Compiles without errors
- Exports all domain types
- Unit tests for invariants and value objects
- No PostgreSQL, S3, Express, AI models, queues

packages/domain/package.json

@@ -0,0 +1,22 @@
+{
+  "name": "@landvex/domain",
+  "version": "0.1.0",
+  "description": "LandveX domain model - Control Intelligence Platform",
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "scripts": {
+    "build": "tsc",
+    "test": "jest",
+    "lint": "eslint src/**/*.ts"
+  },
+  "devDependencies": {
+    "typescript": "^5.0.0",
+    "jest": "^29.0.0",
+    "@types/jest": "^29.0.0",
+    "ts-jest": "^29.0.0",
+    "eslint": "^8.0.0",
+    "@typescript-eslint/eslint-plugin": "^6.0.0",
+    "@typescript-eslint/parser": "^6.0.0"
+  },
+  "dependencies": {}
+}