Fix anchor CI: run keys sync before build for 1.0.0 compatibility

Anchor 1.0.0 added a hard check that declare_id!() matches the keypair
file, failing the build on mismatch. Running 'anchor keys sync' first
fixes the mismatch in-place before the build runs.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: mikemaccana

.github/workflows/anchor.yml

@@ -136,6 +136,9 @@ jobs:
               return 1
             fi
 
+            # Sync program IDs (Anchor 1.0.0 requires keypair and declare_id! to match)
+            anchor keys sync
+
             # Run anchor build
             if ! anchor build; then
               echo "::error::anchor build failed for $project"