docs(agents): require upstream author credit for mirrored code (#27504)

.agents/docs/self-review-rules.md

@@ -24,6 +24,12 @@ Every change gets the full review; go deeper the farther it can reach:
 - SQL: beyond the usual review, watch for the classic side effect — a DELETE/UPDATE whose
   WHERE clause catches rows it shouldn't.
 
+## Upstream attribution
+
+Any changed code, mechanism, or data mirrored from another core must carry that upstream commit's
+author via `--author` (extras as `Co-authored-by`) with the template's cherry-pick box checked; a
+missing credit is a finding.
+
 ## In-game testing
 
 PRs are expected to be tested in-game, which the reviewer cannot do. Never guess what the

AGENTS.md

@@ -10,6 +10,7 @@ AzerothCore is a C++ MMORPG server emulator for World of Warcraft 3.3.5a (WotLK)
 - **Prefer live-stack e2e to debug/validate player-visible behaviour** when a local auth+world+MySQL stack is available (protocol, combat, quests, loot, death, multi-bot). See `e2e/README.md` and AzerothGhost `e2e/LLM_GUIDE.md`. Do not invent e2e for pure unit-sized logic — see `.agents/docs/e2e-policy.md`.
 - **Scratch e2e only under `e2e/local/`** (gitignored). Never commit throwaway debug tests. Promote keepers into `e2e/suites/` or `e2e/smoke/`.
 - Planning docs go in `.agents/plans/<task-slug>/` (gitignored), named `<task-slug>.<TYPE>.md` (`PLAN`, `REQUIREMENTS`, `ANALYSIS`, …).
+- **Credit upstream authors.** Code, a mechanism, or data mirrored from another core (TrinityCore, cMaNGOS, …) is committed with `--author` naming the original commit's author (extra sources as `Co-authored-by`), even when rewritten against AC or confirmed by own sniffs; find them in the upstream file's commit history.
 
 ## Mandatory reading per task