feat: add deploy pipeline and switch Dockerfile to COPY-based build

Add deploy_server Drone pipeline that builds and pushes the Docker image
to Gitea Container Registry, then deploys to VPS via SSH. Switch
Dockerfile from git clone to COPY-based build for CI compatibility and
better layer caching. Change exposed port to 3001.

apps/server/docker/Dockerfile

@@ -1,15 +1,17 @@
 FROM node:alpine AS build
 
-RUN apk add --no-cache git
-
-ARG BRANCH=main
 WORKDIR /app
-RUN git clone --branch ${BRANCH} --depth 1 https://gitea.gilmour109.de/Gilmour109/calchat.git .
 
-RUN npm ci --workspace=@calchat/server --workspace=@calchat/shared --include-workspace-root
+COPY package.json package-lock.json ./
+COPY packages/shared/package.json ./packages/shared/
+COPY apps/server/package.json ./apps/server/
 
-RUN npm run build --workspace=@calchat/shared && \
-    npm run build --workspace=@calchat/server
+RUN npm ci -w @calchat/server -w @calchat/shared --include-workspace-root
+
+COPY packages/shared/ packages/shared/
+COPY apps/server/ apps/server/
+
+RUN npm run build -w @calchat/shared && npm run build -w @calchat/server
 
 FROM node:alpine
 
@@ -19,11 +21,11 @@ COPY --from=build /app/package.json /app/package-lock.json ./
 COPY --from=build /app/packages/shared/package.json packages/shared/
 COPY --from=build /app/apps/server/package.json apps/server/
 
-RUN npm ci --omit=dev --workspace=@calchat/server --workspace=@calchat/shared --include-workspace-root
+RUN npm ci --omit=dev -w @calchat/server -w @calchat/shared
 
 COPY --from=build /app/packages/shared/dist/ packages/shared/dist/
 COPY --from=build /app/apps/server/dist/ apps/server/dist/
 
-EXPOSE 3000
+EXPOSE 3001
 
 CMD ["node", "apps/server/dist/app.js"]