feat: generate metadata from the plan

Summarize the changes

• feat: generate metadata from the plan

Ensure that

• New code is covered by unit and integration tests.
• Related issues would be automatically closed with gitlab's closing pattern.
• Public modules are documented (check the rendered version with cargo doc --open).
• [ ] (if PEST grammar is changed) EBNF grammar reflects these changes (check the result with railroad diagram generator.

Next steps

• Cherry-pick to: none
• Update sbroad submodule in picodata/picodata.
• (if EBNF grammar is changed) create a follow-up issue in picodata/docs.

Closes #632 (closed)

Picodata update with tests: picodata!1067 (merged)