Switch ocm-kit import path to open-component-model/community monorepo

[cbrgm]

Summary

ocm-kit has moved to the Open Component Model community monorepo:
https://github.com/open-component-model/community/tree/main/ocm-kit

We should switch our dependency and all references from the old location
(go.opendefense.cloud/ocm-kit / github.com/opendefensecloud/ocm-kit) to the
new upstream location.

Open question (needs confirmation first): The new location is a subdirectory of a monorepo, so the Go module path
changes, not only the GitHub URL. We need to confirm the exact import path
before starting, e.g.:

• github.com/open-component-model/community/ocm-kit, or
• a retained vanity path (go.opendefense.cloud/ocm-kit).

We also need to confirm that the helmvalues package still lives at the same
relative path, and which module version/tag to pin.

What needs to change

Code

• go.mod / go.sum -> replace go.opendefense.cloud/ocm-kit v0.1.4
• pkg/discovery/handler/helm.go:14 -> import go.opendefense.cloud/ocm-kit/helmvalues

Docs (links + CLI examples pointing at github.com/opendefensecloud/ocm-kit)

• docs/user-guide/helm-values-templating.md (multiple links + ocm-kit CLI examples)
• docs/developer-guide/adrs/011-component-dependencies.md
• docs/developer-guide/adrs/013-catalog-chaining.md
• docs/developer-guide/discovery_pipeline.md (verify)

Notes

• The Makefile / e2e references to opendefense.cloud/ocm-demo are the OCM CLI
  demo component, not the kit library out of scope.

[cbrgm]

Related to open-component-model/community#10