feat: add Docker Compose support for running Boop permanently in background

[kaihere14]

Summary

Add a docker-compose.yml + Dockerfile so users can run Boop as a persistent
background service instead of keeping a terminal open with npm run dev.

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Motivation

The current npm run dev workflow is great for first-run and development but doesn't
work well for always-on use. If you close your terminal or reboot, the agent goes
offline. A Docker Compose setup lets users run Boop like a proper background service —
survives reboots, restarts on crash, and has clean log management.

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Proposed solution

Add the following files to the repo root:

• Dockerfile — builds the server (server/index.ts via tsx)
• Dockerfile.debug — builds and serves the Vite debug dashboard
• docker-compose.yml — orchestrates both services with restart: unless-stopped
• DOCKER.md — setup guide

Services in the compose file

Service	What it does
server	Express backend + agent loop, port 3456
debug	Vite debug dashboard, port 5173
tunnel	Cloudflare Tunnel sidecar — stable public URL for Sendblue webhook (opt-in via --profile tunnel)

Key design decisions

Claude Code credentials — the container mounts ~/.claude read-only from the host
so the Agent SDK can reuse the existing session. No ANTHROPIC_API_KEY required.

Convex is not containerized — it's a hosted cloud service. Users just need to have
run npx convex deploy once; no local Convex process is needed at runtime.

Cloudflare Tunnel instead of ngrok — free ngrok rotates URLs on restart which breaks
the Sendblue webhook. The tunnel service offers a stable URL as an opt-in
--profile tunnel sidecar. Users on a VPS can skip it and just set PUBLIC_URL directly.

npm run dev is untouched — purely additive. Existing dev workflow stays exactly as is.

Basic usage after merging

# one-time: sign in to Claude Code on the host, deploy Convex
claude
npx convex deploy

# run permanently in background
docker compose up -d

# with Cloudflare Tunnel for stable Sendblue webhook
docker compose --profile tunnel up -d

# update after git pull
docker compose up -d --build

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What this is NOT

• Not a production hardening PR — no secrets manager, no multi-arch builds, no k8s manifests
• Not changing any server code — pure infra files
• Not breaking any existing workflow

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Checklist before opening a PR

• Dockerfile builds clean from repo root
• docker compose up -d starts server + dashboard successfully
• ~/.claude mount is documented clearly (common gotcha)
• DOCKER.md covers the Cloudflare Tunnel setup steps
• CHANGELOG.md updated under Unreleased (non-breaking addition)
• Works on a fresh clone with only .env.local already filled in

[thegreatalxx]

hey @kaihere14 working on this rn!

[kaihere14]

hey @kaihere14 working on this rn!

Hey, I’m almost done setting up the Docker environment and will raise a PR soon so you can work on something else in the meantime.