Ship prebuilt binaries and a --tunnel flag for easy local runs

[aterga]

What & why

Makes the server downloadable and runnable with as few dependencies and as little compile time as possible — collapsing this:

git clone https://github.com/aterga/imcp2 && cd imcp2
cloudflared tunnel --url http://localhost:8000            # copy the printed URL
PUBLIC_URL="https://<name>.trycloudflare.com" cargo run   # restart with it set

into this:

curl -fsSL https://github.com/aterga/imcp2/releases/latest/download/imcp-$(uname -s)-$(uname -m).tar.gz | tar xz
./imcp --tunnel

No clone, no Rust toolchain, no compile, no copy-paste, no restart.

Changes

1. Prebuilt binaries via GitHub Releases (.github/workflows/release.yml)

• On every v* tag, builds a self-contained binary for linux x86_64/arm64 and macOS x86_64/arm64, packages each as imcp-<uname -s>-<uname -m>.tar.gz + .sha256, and attaches them to a draft release for review. Also runs on workflow_dispatch (artifacts only, no release).
• The binary is already fully self-contained — the only static assets (Candid cheat sheets + HTML pages) are baked in at compile time via include_str!, so each asset is just one executable.
• Built natively per target (no cross-compiling): the rustls crypto backend (aws-lc-sys) needs cmake/clang and resists cross/musl builds, so native runners are the reliable path. Linux gnu binaries target glibc 2.35+ (Ubuntu 22.04 runner); the Dockerfile remains the option for older distros.

2. --tunnel flag (src/tunnel.rs, src/main.rs)

• The server spawns cloudflared tunnel --url http://localhost:<port>, scrapes the https://<name>.trycloudflare.com URL from its output, and sets PUBLIC_URL from it before anything reads PUBLIC_URL (allowed_hosts() and auth::base_url()).
• cloudflared is kept alive (kill_on_drop) for the server's lifetime; its stderr is drained so the tunnel never stalls. A missing binary produces a clear install hint instead of a stack trace. If PUBLIC_URL is already set, --tunnel is a no-op.
• Adds --help / --version while wiring up arg parsing.

3. README

• Documents the download-a-binary flow and the --tunnel one-liner.

Testing

• cargo check --locked --all-targets and cargo build --locked — clean (only the pre-existing tool_router dead-code warning).
• cargo test tunnel:: — 5 URL-extraction unit tests pass.
• Manual: --help, --version, unknown-flag (exit 2), and --tunnel with cloudflared absent (clean install-hint error) all verified.

Note: the release workflow itself can only be exercised by pushing a v* tag / running it from the Actions tab — it hasn't run in CI yet.

🤖 Generated with Claude Code

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Generated by Claude Code

[Copilot]

Pull request overview

Adds a smoother “download-and-run” story for the server by (1) publishing prebuilt release binaries and (2) introducing a --tunnel flag that auto-provisions a Cloudflare quick tunnel and derives PUBLIC_URL during startup.

Changes:

• Add --tunnel, --help, and --version CLI handling; implement Cloudflare quick-tunnel spawning + URL scraping.
• Add a GitHub Actions release workflow that builds and packages per-platform tarballs + SHA256 files for GitHub Releases.
• Update README to document the prebuilt-binary flow and the --tunnel one-liner; expand Tokio features needed for process IO/timeouts.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/tunnel.rs	New module to spawn cloudflared, drain logs, and extract the trycloudflare.com URL with tests.
src/main.rs	Adds basic CLI parsing and wires --tunnel into startup before PUBLIC_URL is read.
README.md	Documents downloading release tarballs and using --tunnel for a public URL.
Cargo.toml	Expands Tokio feature set to support tokio::process, IO, timeouts, and channels.
.github/workflows/release.yml	New workflow to build/package/upload per-platform release artifacts and create/update a draft GitHub Release.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 5 comments.