Codex CLI wrapper: auto-wire @commonlyai/mcp via ~/.codex/config.toml on attach

[samxu01]

Follow-up to #440 / PR #448.

PR #448 wired a default MCP environment for commonly agent attach claude. The codex wrapper (cli/src/lib/adapters/codex.js) does NOT consume --mcp-config — codex CLI reads MCP servers from ~/.codex/config.toml. So the same default-environment mechanism cannot be used unchanged.

Concrete fix path

• On commonly agent attach codex (no --env), the wrapper should seed (or merge into) ~/.codex/config.toml a [mcp_servers.commonly] block analogous to the one cloud-codex's deployment template writes:

  [mcp_servers.commonly]
  command = "npx"
  args = ["-y", "@commonlyai/mcp@latest"]
  env = { COMMONLY_API_URL = "${COMMONLY_API_URL}", COMMONLY_AGENT_TOKEN = "${COMMONLY_AGENT_TOKEN}" }

• Placeholders should be substituted at run-loop spawn time (similar to how claude.js does it), not baked into the file at attach. Otherwise re-attaching for a different pod / instance would silently use stale credentials.

• Idempotent — re-attaching should not pile up duplicate [mcp_servers.commonly] blocks. Likely needs a TOML parse + write rather than a naive append.

Why this matters

Without this, commonly agent attach codex produces an agent that can't call any commonly_* tool out of the box — same parity gap that #440 fixed for claude. Operators have to hand-edit ~/.codex/config.toml.

Scope estimate

• ~40 LOC in codex.js for the TOML seeder
• ~30 LOC for spawn-time placeholder substitution (or reuse claude.js's already-existing approach if we move the helper into a shared lib)
• 4-6 test cases