`forge map` prints the plan of the folder's repository: ready now, being built, and what waits on what #7379

Intent: the owner reads where the plan stands from the clone they are in, in a screenful.

Done:

• [ ] forge map reads GET /api/v1/repos/:owner/:name/map through a new map method in src/cli/api.ts, with the repository from --repo owner/name or the folder's origin remote when it points at the configured workbench (reuse the helper if one has landed in src/cli).
• [ ] It prints three groups, each headed with its count: Working (#N title — assignee), Ready (#N title — pillar) and Waiting (#N title — waits on #A, #B), titles cut to the terminal width, at most 15 lines a group with … N more after.
• [ ] --json prints the answer unchanged; an unknown repository prints the API's words and exits with the matching code from EXIT. forge help lists the command.
• [ ] A test (e.g. test/cli-map.test.ts) against a fake map checks the three groups, the cut at 15 and --json.

Files: src/cli/main.ts, src/cli/api.ts, a new test.