feat(16-02): create shared types package

- @codewalk-district/shared exports AppRouter and entity types
- Re-exports Initiative, Phase, Plan, Task, Agent, Message from schema
- Types-only package with no runtime dependencies
- TypeScript resolves directly (no build step needed)

packages/shared/package.json

@@ -0,0 +1,10 @@
+{
+  "name": "@codewalk-district/shared",
+  "version": "0.0.1",
+  "type": "module",
+  "main": "./src/index.ts",
+  "types": "./src/index.ts",
+  "exports": {
+    ".": "./src/index.ts"
+  }
+}

packages/shared/src/index.ts

@@ -0,0 +1,2 @@
+export type { AppRouter } from './trpc.js';
+export type { Initiative, Phase, Plan, Task, Agent, Message } from './types.js';

packages/shared/src/trpc.ts

@@ -0,0 +1 @@
+export type { AppRouter } from '../../../src/trpc/router.js';

packages/shared/src/types.ts

@@ -0,0 +1 @@
+export type { Initiative, Phase, Plan, Task, Agent, Message } from '../../../src/db/schema.js';

packages/shared/tsconfig.json

@@ -0,0 +1,13 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "module": "NodeNext",
+    "moduleResolution": "NodeNext",
+    "strict": true,
+    "declaration": true,
+    "outDir": "dist",
+    "rootDir": "../..",
+    "skipLibCheck": true
+  },
+  "include": ["src"]
+}