ci: optimizations

Author: evansims

.github/workflows/ci.yml

@@ -7,6 +7,9 @@ on:
     branches: [main]
   pull_request:
     branches: [main]
+  schedule:
+    # Nightly at midnight UTC (for coverage)
+    - cron: "0 0 * * *"
 
 # Cancel in-progress runs when new commits are pushed
 concurrency:
@@ -262,12 +265,12 @@ jobs:
           path: target/nextest/ci/junit.xml
           retention-days: 7
 
-  # Test code coverage (reuses build cache)
+  # Test code coverage (nightly only to reduce CI costs)
   coverage:
     name: Code Coverage
     needs: build
     runs-on: ubuntu-latest
-    if: github.actor != 'dependabot[bot]'
+    if: github.event_name == 'schedule'
     continue-on-error: true
     permissions:
       contents: read