Bump all internal packages from 1.0.4 / 1.0.3 → 1.2.0 for the v1.2
"Agent-native Analytics" release.

Includes (merged via PRs #11, #12, #15, #16 + direct commit):
- Tracks A+B: packages/dql-mcp + App artifact (f929743)
- Track C:   chat cell + BYOK providers (#11)
- Track D:   local scheduler (dql schedule) (#12)
- Track E:   CXO daily digest emitter (#15)
- Tracks F+G: retire Workbook + agent-facing block metadata (#16)