feat: add a README editor to the Create Bundle wizard

[JasonPaff]

Summary

Follow-up 1 from #5 / #4. Bundles published from the web always shipped without README.md because the Create Bundle wizard hard-coded readme: '' on publish. The publish path already supported a README; only the UI was missing. This is likely why the #4 reporter put README content into setup instructions.

Changes

• README step in the Create Bundle wizard, between Assets and Setup (Metadata → Assets → README → Setup → Review), mirroring the asset Contribute wizard: markdown textarea with a live preview. Optional, like Setup. The step copy spells out that README is the bundle's overview page and Setup is post-install steps.
• Review step shows a "README provided / No README" row.
• Publish passes draft.readme through to publishBundle, which appends README.md to the payload. The README stays a sibling file and never lands in bundle.json.
• Draft state: readme added to the draft, the persisted-draft schema (defaults to '' so drafts saved before this step still load), and the edit/new-version seed.
• Edit / New version on the bundle page now seeds the wizard with the current README so a new version starts from the existing one.
• Also commits docs/bundle-readme-followups.md, the handoff notes for the three follow-ups.

Tests

• Wizard walk-through types a README, asserts the live preview, the readme publish argument, and that neither the review bundle.json nor the publish manifest contains a readme key.
• New cases: skipping the README step publishes an empty README; the editor is seeded from navigation state; legacy persisted drafts without readme load; BundleDetail Edit / New version seeds readme when present and omits it when absent.

Verification

• pnpm lint, pnpm typecheck, pnpm test (29 files, 295 tests) all green.
• npx prettier --check clean on the touched files. Repo-wide format:check still has the pre-existing CRLF noise from main.
• Not manually exercised against the dev API.

Related

• API: bundle zip now includes the bundle README (Azure DevOps PR in Emergent.AgenticToolkit).
• CLI: EmergentSoftware/agentic-toolkit-cli PR for atk info README rendering.

🤖 Generated with Claude Code

https://claude.ai/code/session_011nojgR3M3ZNo3BfyTZdWTz