fix(helm): allow host[:port][/path] form in global.imageRegistry schema (#4686)

The values.schema.json constrained global.imageRegistry to JSON Schema
hostname format (RFC 1123), which forbids '/'. That rejected the
host+path form required by Artifactory virtual repos, Harbor projects,
GCR (gcr.io/project-id), and ECR-with-namespace — all of which the
chart's image-rendering helper already supports (it prints '%s/%s:%s').

Drop the format constraint and document the supported shapes. Matches
the bitnami common-chart convention of validating image registry as a
plain string and deferring to Docker for the actual reference parse.

Author: waleedlatif1

helm/sim/values.schema.json

@@ -8,8 +8,7 @@
       "properties": {
         "imageRegistry": {
           "type": "string",
-          "format": "hostname",
-          "description": "Global Docker image registry"
+          "description": "Global Docker image registry (host[:port][/path]). Supports plain hosts (registry.example.com), host:port (registry.example.com:5000), and host+path forms used by Artifactory virtual repos, Harbor projects, GCR (gcr.io/project-id), and ECR-with-namespace."
         },
         "useRegistryForAllImages": {
           "type": "boolean",