docs: add CLI and Unity surface research and product glossary

[callumflack]

Summary

Records the CLI/all-Unity comparison, shared product language, and a latest-dev recheck. Corrects the stale MCP-page and grant-union claims, distinguishes the remaining delivery-completion question, and assesses shared plumbing alongside public source and independent releases.

GLOSSARY.md
research/261009-cli-unity-surfaces-discrepancy-research.md  original baseline + dated correction
research/261010-cli-unity-team-response-review.md          current findings + repository/release assessment

Evidence

• Before: The dated comparison used the design branch and reported missing MCP-page and grant-union work.
  After: The recheck covers all ten findings against Unity dev 6cefcc41, records the relevant successful 8 October production deployment, and preserves the original baseline and verbatim discussion.
• All 96 original and 86 follow-up pinned source references were checked against the recorded snapshots.
• 35 existing focused Web MCP/grant-union tests passed against the dev snapshot. Real authenticated consent and cross-host collection remain explicitly unproved.
• Prettier and staged whitespace checks pass for the two updates.

Merge Danger

Door: Two-way

Blast Radius: Documentation

Three Markdown files in the full PR. No runtime or dependency changes; architectural directions remain proposals.