feat(helm): add optional Gateway API HTTPRoute support

Add disabled-by-default HTTPRoute support with configurable parent references,
hostnames, paths, annotations and optional timeouts. Route to the existing TREK
Service and keep Ingress support unchanged, including simultaneous use.

Document configuration and extend the existing Helm Chart & Compose job with
HTTPRoute render variants and strict validation using a pinned CRDs catalog.

Approved on Discord:
https://discord.com/channels/1488298068427411591/1553537637455761500

Validation: strict Helm lint, 37 manifests validated without errors or skipped
resources, and both Compose configuration checks passed locally.
Live Gateway WebSocket and streamed assistant response checks were not performed
because no Kubernetes test cluster was configured.

.github/workflows/test.yml

@@ -1270,9 +1270,24 @@ jobs:
             --set 'extraVolumeMounts[0].readOnly=true' \
             --set probes.liveness=null \
             > "$out/variants.yaml"
+          helm template trek charts/trek \
+            --set httpRoute.enabled=true \
+            --set 'httpRoute.parentRefs[0].name=gateway' \
+            > "$out/http-route.yaml"
+          helm template trek charts/trek \
+            --set ingress.enabled=true \
+            --set fullnameOverride=custom-trek \
+            --set service.port=8080 \
+            --set-json 'httpRoute={"enabled":true,"parentRefs":[{"name":"gateway","namespace":"gateway-system","sectionName":"https"}],"hostnames":["trek.example.com"],"paths":["/","/api"],"annotations":{"example.com/note":"custom route"},"timeouts":{"request":"0s","backendRequest":"0s"}}' \
+            > "$out/http-route-variants.yaml"
 
       - name: Check the manifests against the Kubernetes schemas
-        run: kubeconform -strict -summary "$RUNNER_TEMP"/rendered/*.yaml
+        # The pinned Gateway API schema adds HTTPRoute validation without skipping unknown resources.
+        run: >-
+          kubeconform -strict -summary
+          -schema-location default
+          -schema-location 'https://raw.githubusercontent.com/datreeio/CRDs-catalog/041baf4c1d3740ca21461cab765e7432ecd073ef/{{.Group}}/{{.ResourceKind}}_{{.ResourceAPIVersion}}.json'
+          "$RUNNER_TEMP"/rendered/*.yaml
 
       - name: Check every compose file
         run: |