[JacobStephens2]

Summary

Records the #1468 Custom runner grilling, glossary updates, and ADR 0032 ahead of Spec #1468's Tickets (#2188–#2192). Part of #1468.

 GLOSSARY.md
+  Custom runner     setup outside thirdshift run by an Arm on a Trial in place of a thirdshift build and Process
   Arm               + either a thirdshift build or a Custom runner (Baseline, Candidate, or both)
   Trial             + or a Custom runner's work and sessions on the Ticket
   Experiment        + or on the Eval suites named for it
   Credentials       + Custom runner provider keys reserved for Trials
 docs/adr/
+  0032-custom-runners-run-inside-one-trial-sandbox.md
 docs/grill-with-docs/done/
+  1468-custom-runner-arm.md   # Rounds 1–3 (Q1.1–Q3.4), settled design, and published Spec/Tickets

Evidence

Execution evidence

• Before: GLOSSARY.md required every Arm to carry a thirdshift build and Process, and scripts/affected-tests main failed on npm test --prefix site with ERR_MODULE_NOT_FOUND (marked) before installing site dependencies.
  After: after npm ci --prefix site, npm test --prefix site passed (docs:check, glossary/manual checks, and Playwright suite), and git diff origin/main --check is clean.
• The Linux-only Rust targets (share_card, site_deploy) run in GitHub Actions CI (thirdshift targets Linux only on macOS).

Merge Danger

Door: two-way

Blast Radius: none

Documentation, glossary, and ADR updates recording #1468's settled design for Tickets #2188–#2192.