feat: initial SleepGuard implementation

Wake-on-demand proxy + agent system with SvelteKit dashboard.
Monorepo: shared types, proxy (Hono + http-proxy), agent (monitors + locks), web (SvelteKit SPA).

Co-Authored-By: Claude <noreply@anthropic.com>

package.json

@@ -0,0 +1,20 @@
+{
+  "name": "sleepguard",
+  "private": true,
+  "workspaces": [
+    "packages/*",
+    "packages/proxy/web"
+  ],
+  "scripts": {
+    "dev:agent": "yarn workspace @sleepguard/agent dev",
+    "dev:proxy": "yarn workspace @sleepguard/proxy dev",
+    "dev:web": "yarn workspace @sleepguard/web dev",
+    "build": "yarn workspaces foreach -At run build",
+    "build:shared": "yarn workspace @sleepguard/shared build",
+    "build:agent": "yarn workspace @sleepguard/agent build",
+    "build:proxy": "yarn workspace @sleepguard/proxy build",
+    "build:web": "yarn workspace @sleepguard/web build",
+    "typecheck": "yarn workspaces foreach -At run typecheck"
+  },
+  "packageManager": "yarn@4.6.0"
+}