docs/CLI.md says every `forge` command with one example each, and a test fails when `forge help` lists one it does not #7372

Intent: a person or an agent finds how to drive the forge from a shell in one page, and it stays true as commands are added.

Done:

• [ ] A new docs/CLI.md: how to install and log in, then one section per command forge help prints today (login, logout, whoami, sync, status, ls, pin, unpin, open, ui and any other it lists), each with what it does, its flags and one example with its output.
• [ ] docs/DEVELOP.md links it in one line.
• [ ] A test (e.g. test/cli-docs.test.ts) captures forge help's output (run main from src/cli/main.ts with help and a capturing out, or spawn it) and fails naming each command that has no ## forge <command> heading in docs/CLI.md.

Files: docs/CLI.md (new), docs/DEVELOP.md, a new test.

Risk: other pulls adding commands will meet this test; its failure message must say exactly which heading to add.