M2 docs, examples, and QA matrix for table formatting

Problem

Ship author-facing documentation (not only the initiative spec) so dashboard authors can use style.table / style.columns on table charts confidently: column-ID-first rules, what is not configurable at “cell” scope, links and templates, visual spark/bar, Vega-Lite-shaped value formatting, duplicate-key errors, and Jinja/SQL helper patterns. Pair that with reference YAML and a QA matrix that exercises common and edge-case paths.

Context

• The table-formatting initiative needs author-facing docs, not just internal architecture notes.
• Authors need copy-paste examples that mirror the intended schema and constraints.
• QA needs an explicit behavior matrix so regressions are caught consistently across formatting and linking paths.

Possible Solutions

• A - Rely on initiative specs and scattered examples in tests: low effort, but poor discoverability.
• B - Write docs only after the entire table surface is complete: delays adoption and review quality.
• C - Recommended: ship docs, reference YAML, and a QA matrix together so authors and reviewers use the same contract.

Plan

1. Extract the final author-facing concepts and limits from the initiative spec.
2. Write a compact set of examples for styling, linking, visuals, and formatting.
3. Build a QA matrix covering common and edge-case behaviors for those examples.
4. Publish the docs and use the matrix to validate the first implementation pass.

Implementation Progress

QA Exploration

• [ ] QA exploration completed (or N/A for non-UI tasks)

Review Feedback

• [ ] Review cleared