feat: mock params setting

Summarize the changes

• feat: mock params setting

Closes #661 (closed).

Ensure that

• New code is covered by unit and integration tests.
• Related issues would be automatically closed with gitlab's closing pattern (Closes #1, #2).
• 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
• picodata follow-up: picodata!1051 (merged)