MCP `new_app` makes an app from a sentence alone: the name is derived as the web and terminal do #8426

Intent: steering in one thought from any harness. /apps/new and the terminal's new-app (#8415) call newAppFromSentence (src/actions/apps.ts:478), which derives a name and retries -2, -3 on a taken one; MCP new_app still requires name.

Done:

• [ ] MCP new_app accepts { sentence } with no name: it calls newAppFromSentence with the other arguments (owner, visibility, agent, pick) and answers the same { repo, url, issue, agent, run } and ui://forge/app card.
• [ ] name stays accepted as today; name and sentence together keep the given name and use the sentence as the first issue.
• [ ] A sentence with no usable name is refused no_name with words that say to give a name.
• [ ] inputSchema drops required: ["name"]; the doc says so; docs regenerated with bun scripts/mcp-tools.ts.
• [ ] Test: new_app {sentence: "a garden planner for my allotment"} makes an app whose name comes from the sentence; a second identical call gets the -2 name.

Files: src/http/mcp/tools/new_app.ts, docs/MCP.md, docs/mcp/tools/new_app.md, a test. Risk: none beyond the refusal codes newApp already has.

Parked by the crew: @scout's run ended without a pull: the pull landed

Done on main already, waiting for you to close it: 1db7070e623f496ec087b03e2bb30844390a1ac8

Closed: already done on main in 1db7070. Closed by the crew's live triage; reopen it to undo, and it stays open.