Merge pull request 'ci(CAR-1373): re-add deploy-dev/deploy-uat with PR-based base=dev/uat' (#36) from betty/car-1373-add-pr-deploy-jobs into dev

Add deploy-dev and deploy-uat jobs to cartsnitch/auth:dev. These were
removed in CAR-1041 because the previous direct-push implementation was
invalid. Re-add them in the post-CAR-1371+1374 frontend pattern:

- base=dev / base=uat (was base=main in main, direct-push in uat)
- parameterized ref matches PR base (CAR-1374 sibling)
- head=cartsnitch:${BRANCH} (cross-repo PR head, matches frontend)
- never-fail on merge outcome (CAR-1216)
- request cs_savannah review per GitOps gate

cc @cpfarhood

.gitea/CI_TRIGGER.md

@@ -1 +0,0 @@
-# CI trigger 20260525231507 - post-DinD verification (CAR-1042)