AGENTS.md: one workflow for every change (touched-crate tests and clippy, self-merge, CI once per merge on main) (#53)

Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm

Co-authored-by: jyviko <2501648+jyviko@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

docs/verification.md

@@ -25,7 +25,7 @@ Rules:
   still passes), and writes `docs/oracle.md` with the table of cases, sources, errors and status.
 - A fixture is updated only deliberately (`--bless`), in a PR that says why the result moved
   (a better element, a finer default mesh), never to hide a regression.
-- The theory suite is the gate for every PR; experiment and benchmark cases run in CI too, with
+- The theory suite is the gate for every merge; experiment and benchmark cases run in CI too, with
   their cited tolerances.
 
 ## The case format