dev: add parallel dev environment under /docker/dev

Near-1:1 clone of the prod remote-access stack, isolated on a new external
dev_edge network and fronted by the same shared Caddy instance (dual-homed on
edge + dev_edge). Dev is manual-start (not on boot).

- Hostnames: app-dev / api-dev .linumiq.net, tunnels under *.dev.linumiq.net,
  dev tunnel ingress on port 7001.
- Dev Supabase (project supabase-dev, *-dev containers), web, frps, redis,
  stripe-stub, bandwidth-worker with fresh independent secrets (gitignored).
- Shared Caddyfile: app-dev -> web-dev, api-dev -> dev kong (+webhook block),
  *.dev -> frps-dev vhost. Caddy compose dual-homed on dev_edge.
- On-demand-TLS authorizer (prod check-subdomain, in gitignored volumes/)
  extended additively: app-dev/api-dev -> 200; *.dev delegated to the dev
  authorizer. Prod allow-list logic unchanged.
- dev.sh manual up/down/ps helper; README documents topology + secrets.

Secrets, frps.toml, volumes/, web worktree and data dirs are gitignored.

dev/stripe-stub/docker-compose.yml

@@ -0,0 +1,21 @@
+name: stripe-stub-dev
+services:
+  stripe-stub:
+    build: .
+    image: stripe-stub-dev:1.0.0
+    container_name: stripe-stub-dev
+    restart: unless-stopped
+    security_opt:
+      - no-new-privileges:true
+    env_file: .env
+    networks:
+      - dev_edge
+    healthcheck:
+      test: ["CMD", "python", "-c", "import urllib.request,sys; sys.exit(0 if urllib.request.urlopen('http://127.0.0.1:4242/health').status==200 else 1)"]
+      interval: 30s
+      timeout: 5s
+      retries: 3
+
+networks:
+  dev_edge:
+    external: true