revert: remove fork-only changes from release sync

Revert payment/wechat, sora/claude-max cleanup, fork-only migrations,
and cosmetic changes that were brought in by the release sync commit.
Keep only channel-monitor related improvements:
- PublicSettingsInjectionPayload named struct with drift test
- ChannelMonitorRunner graceful shutdown in wire
- image_output_price in SupportedModelChip
- Simplified buildSelfNavItems in AppSidebar
- Gateway WARN logs for 503 branches

backend/internal/service/sticky_session_test.go

@@ -122,8 +122,8 @@ func TestShouldClearStickySession(t *testing.T) {
 		{
 			name: "overloaded account",
 			account: &Account{
-				Status:        StatusActive,
-				Schedulable:   true,
+				Status:       StatusActive,
+				Schedulable:  true,
 				OverloadUntil: &future,
 			},
 			requestedModel: "",