ci: disable cancel-in-progress on pr-title check (#311)

* test: strengthen weak memory recommendation assertion

TestRecommendationEngine_RealisticMemory previously only asserted
that the recommendation was > 0, which passes for literally any
positive value. The test would not catch a regression in the memory
recommendation algorithm.

Now uses RecommendWithExplanation to verify:
- Raw P99 is exactly 256Mi (268435456 bytes)
- Final recommendation is in the expected range (280-350Mi)
- Change filter was not applied (39.8% < 50% cap)
- Recommendation is a decrease from the 512Mi current value

Found by Test Auditor perspective during improvement cycle 2.

Signed-off-by: Sebastien Tardif <sebtardif@ncf.ca>

* ci: cache cert-manager manifest and retry kubectl apply

The E2E setup was downloading cert-manager.yaml from GitHub releases
on every run without caching or retry. When the k3d API server was
temporarily unavailable, kubectl apply failed on OpenAPI validation
and the entire E2E job failed with no recovery.

Changes:
- Add /tmp/cert-manager.yaml to the actions/cache path list so the
  manifest is cached alongside container image tarballs
- Download the manifest to a local file with 3 retry attempts before
  the kubectl apply step
- Wrap kubectl apply in a 3-attempt retry loop with 15s delay

This matches the existing retry pattern used for docker pull (3
attempts, 10s delay) and k3d cluster create (3 attempts, 10s delay).

Signed-off-by: Sebastien Tardif <sebtardif@ncf.ca>

* ci: disable cancel-in-progress on pr-title check

The pr-title workflow uses cancel-in-progress: true, which can leave
a cancelled run as the status check on a PR when two runs trigger
simultaneously. Since this job takes ~1 second, cancellation saves
nothing but can produce a stuck red X (as seen on PR #298).

Setting cancel-in-progress to false avoids the race condition.

Signed-off-by: Sebastien Tardif <sebtardif@ncf.ca>

---------

Signed-off-by: Sebastien Tardif <sebtardif@ncf.ca>

Author: SebTardif

.github/workflows/pr-title.yaml

@@ -9,7 +9,7 @@ permissions:
 
 concurrency:
   group: pr-title-${{ github.event.pull_request.number }}
-  cancel-in-progress: true
+  cancel-in-progress: false
 
 jobs:
   semantic-title: