refactor: restructure bastion as pnpm monorepo (@lab/shared, @lab/bastion, @lab/cli)

- Split into 3 workspace packages: shared (types/constants), bastion (server), cli
- CLI binary renamed from "bastion" to "lab"
- Cross-package imports via @lab/shared and @lab/bastion workspace references
- Extracted BastionConfig, BastionState, HardwareInfo types into @lab/shared
- Added APP_NAME/APP_VERSION constants
- tsconfig.base.json with project references for build ordering
- Root workspace scripts: build, test, typecheck, clean

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

bastion/tsconfig.json

@@ -1,27 +1,8 @@
 {
-  "compilerOptions": {
-    "target": "ES2022",
-    "module": "NodeNext",
-    "moduleResolution": "NodeNext",
-    "lib": ["ES2022"],
-    "strict": true,
-    "esModuleInterop": true,
-    "skipLibCheck": true,
-    "forceConsistentCasingInFileNames": true,
-    "declaration": true,
-    "sourceMap": true,
-    "incremental": true,
-    "noUnusedLocals": true,
-    "noUnusedParameters": true,
-    "noImplicitReturns": true,
-    "noFallthroughCasesInSwitch": true,
-    "noUncheckedIndexedAccess": true,
-    "isolatedModules": true,
-    "resolveJsonModule": true,
-    "rootDir": "src",
-    "outDir": "dist",
-    "types": ["node"]
-  },
-  "include": ["src/**/*.ts"],
-  "exclude": ["node_modules", "dist"]
+  "files": [],
+  "references": [
+    { "path": "src/shared" },
+    { "path": "src/bastion" },
+    { "path": "src/cli" }
+  ]
 }