Start an Epic workspace

Output contract: Collect every required choice explicitly; never infer or preselect; preserve errors, artifacts, and next actions. For suggested actions, pair Shell with the returned Copilot command; honor commandGuidance. If absent, say "Copilot: no verified equivalent"; never invent a slash command.

Boundary: no Story required; cwd=opened Git root or verified repositoryPath from singularity-flow workspace current --json; refuse if neither resolves; never search $HOME/parents.

1. Require the Jira Epic key. Run singularity-flow initiative choices begin start <EPIC-KEY> --json.
2. Present every profile and governed-agent option with Copilot's selectable question UI. Do not infer an answer.
3. Record each answer with singularity-flow initiative choices answer <TOKEN> <CHOICE-ID> <SELECTED-ID> --json.
4. When the receipt is ready, run singularity-flow epic start <EPIC-KEY> --selection-receipt <TOKEN>.
5. The default profile is epic-planning; a user may select a configured full-delivery profile instead.
6. Show the created branch, pinned profile, source Jira identity, commit/push result, complete phase flow, and first deterministic next action.
7. Do not create branches manually or approve any phase.