fr-brainstorminglisted

# fr-brainstorming `superpowers:brainstorming`, wrapped in isolation. Exploration commands, spec drafts, and everything downstream happen in the isolation workspace, so a brainstorm that becomes a build never has to relocate, and a brainstorm that dies leaves the base repo pristine. **Announce at start:** "I'm using fr-brainstorming to design this in isolation." ## 0. Isolation first — hard gate Before ANY command — exploration, measurement, cluster reads included; an operator "start with X" never reorders this: ```bash fr isolation up --branch <feature-branch> [--profile <name>] ``` - Name the branch for the feature now (`feat/<slug>`); the worktree, the eventual PR, and cleanup all key off it. The new `feat/<slug>` is cut from freshly-fetched `origin/<default>` (#322) — pass `--base <ref>` only to stack on something else. - **No devcontainer profile → HARD STOP — but only in devcontainer mode.** Offer to run the fr-init interview immediately; if the operator declines, the brainstorm does not proceed. (Under fr-goal, treat it as a blocker: pause, fr-init, resume.) On a docker-less host that declares `FR_ISOLATION_TARGET=worktree` (or in a prepared external container), `up` succeeds without a profile — no stop, the worktree is the isolation. - From here on, follow the fr-isolation skill's exec-bridge discipline: read/edit files in the worktree, run every command through `fr isolation exec -- ...`. - **Standalone invocation only:** also start the run