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>

packages/proxy/Dockerfile

@@ -0,0 +1,48 @@
+FROM node:22-alpine AS base
+RUN corepack enable
+
+# --- Dependencies ---
+FROM base AS deps
+WORKDIR /app
+COPY package.json yarn.lock .yarnrc.yml ./
+COPY packages/shared/package.json packages/shared/
+COPY packages/proxy/package.json packages/proxy/
+COPY packages/proxy/web/package.json packages/proxy/web/
+RUN yarn install --immutable
+
+# --- Build shared ---
+FROM deps AS build-shared
+WORKDIR /app
+COPY packages/shared packages/shared
+RUN yarn workspace @sleepguard/shared build
+
+# --- Build web ---
+FROM build-shared AS build-web
+WORKDIR /app
+COPY packages/proxy/web packages/proxy/web
+RUN yarn workspace @sleepguard/web build
+
+# --- Build proxy ---
+FROM build-shared AS build-proxy
+WORKDIR /app
+COPY packages/proxy/tsconfig.json packages/proxy/
+COPY packages/proxy/src packages/proxy/src
+RUN yarn workspace @sleepguard/proxy build
+
+# --- Production ---
+FROM base AS production
+WORKDIR /app
+
+COPY package.json yarn.lock .yarnrc.yml ./
+COPY packages/shared/package.json packages/shared/
+COPY packages/proxy/package.json packages/proxy/
+COPY packages/proxy/web/package.json packages/proxy/web/
+RUN yarn workspaces focus @sleepguard/proxy --production
+
+COPY --from=build-shared /app/packages/shared/dist packages/shared/dist
+COPY --from=build-proxy /app/packages/proxy/dist packages/proxy/dist
+COPY --from=build-web /app/packages/proxy/web/build packages/proxy/public/dashboard
+
+WORKDIR /app/packages/proxy
+EXPOSE 47391
+CMD ["node", "dist/index.js"]