Add make install that also registers the server

[jserv]

Installing a checkout meant cargo install, then registering the binary with each agent by hand. make install now builds, installs into BINDIR (~/.local/bin by default), and registers the binary with Claude Code and, when a Codex config exists, with Codex. make register repeats only the registration. An entry either client already has is left alone, since it may carry env or args the user added, and neither entry holds the token.

The binary is staged in BINDIR, ad-hoc signed, run once, then renamed over the target, because copying over an image macOS has already run gets every later exec killed. The Codex entry is appended rather than written by codex mcp add, whose --env stores values instead of forwarding the token by name. The installer runs on the Python 3.9 macOS ships and needs 3.11 only to read a Codex config.

Verified on macOS (GNU Make 3.81):

• python3 tests/install.py passes; it drives make install and make register against stubbed cargo and claude (spaces, quotes, a leading dash and ~ in BINDIR, existing entries in every TOML spelling, invalid configs, failed builds and smoke runs, CODEX_HOME). CI now runs it on Linux and macOS.
• A real make install into a scratch HOME and BINDIR, with /usr/bin/python3 (3.9) and with Homebrew's 3.14: installs, registers once, and a second run leaves both entries as they are.
• SIGTERM during the smoke run exits 1 and leaves no staged file behind.

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Summary by cubic

Adds make install, which builds, installs into BINDIR (default ~/.local/bin), and registers the binary with Claude Code when the claude CLI is on PATH and, when a Codex config exists, with Codex. make register repeats only the registration, replacing manual cargo install and per-agent setup.

Details

• The binary is staged in BINDIR, ad-hoc signed, run once, then renamed over the target; copying over an image macOS has already run leaves a stale codesign blob that kills every later exec. SIGTERM and SIGHUP leave no staged file behind.
• The Codex entry is appended to config.toml rather than written via codex mcp add, whose --env stores values instead of forwarding the token by name.
• An entry either client already has is left as is, since it may carry user-added env or args; neither entry holds the token.
• A Codex config that isn't valid TOML or UTF-8 is left untouched with an error, never a traceback.
• The installer runs on Python 3.9 and needs 3.11 only to read a Codex config; PYTHON=... picks the interpreter. python3 tests/install.py exercises install and register against stubbed cargo and claude and needs Python 3.11, and CI now runs it on Linux and macOS.

^{Written for commit 5290820. Summary will update on new commits.}