feat: complete release readiness work

- consolidate API ownership and remove dead vendor code

- add Stripe billing, learning paths, and public CV hardening

- add migration, recovery, security, audit, and browser gates

docs/cv-builder/workflow.md

@@ -1,3 +1,9 @@
 # workflow
 
-TODO: Complete documentation.
+1. Maintain factual career data in `/career`.
+2. Create or open a named CV variant in `/career/builder`.
+3. Select visible content and apply variant-only overrides.
+4. Choose a theme and customization tokens while previewing live.
+5. Export PDF or explicitly enable a public link.
+
+Autosave appends variant history. AI tools return suggestions only and never save without user action.