chore(docker): bump node 20 → 22

Silences oidc-provider's "Unsupported runtime" warning on every boot.

Dockerfile

@@ -1,5 +1,5 @@
 # Build stage
-FROM node:20-alpine AS builder
+FROM node:22-alpine AS builder
 
 WORKDIR /app
 COPY package*.json ./
@@ -10,7 +10,7 @@ RUN npm run build
 # Production stage — only the self-contained .output is needed.
 # bash + curl are added so Dokploy scheduled tasks (which wrap commands in
 # `bash -c "..."`) can run; alpine ships only ash and has no curl by default.
-FROM node:20-alpine
+FROM node:22-alpine
 RUN apk add --no-cache bash curl
 WORKDIR /app
 COPY --from=builder /app/.output .output