fix: accept no-op pushes where old_oid == new_oid

Fixes race condition where user's push becomes no-op after state event
is applied between fetch and push. Now accepts these as successful
no-ops, matching Git's 'Everything up-to-date' behavior.

- Add early detection in get_state_authorization_for_specific_owner_repo
- Return success for all-noop pushes without requiring purgatory event
- Document behavior in inline-authorization.md

1 files changed, 4 insertions, 0 deletions

diff --git a/docs/explanation/inline-authorization.md b/docs/explanation/inline-authorization.md
index 7081f63..80bd98f 100644
--- a/docs/explanation/inline-authorization.md
+++ b/docs/explanation/inline-authorization.md
@@ -352,6 +352,10 @@ pub async fn authorize_push(
    - If no event found, create placeholder (git-data-first scenario)
    - Collect PR events from purgatory for post-push processing
 
+**No-Op Push Acceptance:** Pushes where all refs have `old_oid == new_oid` are accepted without requiring a purgatory state event, matching Git's "Everything up-to-date" behavior and avoiding race condition rejections.
+
+---
+
 ## State Event Authorization
 
 State events (kind 30618) undergo authorization checks at three points (defense-in-depth):