CBP-47071: make the 'create-namespace' helm install input configurable, defaults to 'true'

[pinaki124]

Add create-namespace input and release-revision output

Summary

• Added a create-namespace input (default true) that controls whether Skaffold creates the target namespace if it does not exist. Previously this was hardcoded to true with no way to opt out.
• Added a release-revision output that exposes the Helm release revision number after a successful install or upgrade. Returns an empty string for dry-run executions.
• Added workflow tests covering three create-namespace scenarios: false into an existing namespace (positive — expects a revision), true into a new namespace (positive — expects a revision), and false into a missing namespace (negative — expects no revision).

Test plan

• install a helm chart with create-namespace set to false into existing namespace — verifies release-revision is non-empty
• install a helm chart with create-namespace set to true into new namespace — verifies release-revision is non-empty in a freshly created namespace
• install a helm chart with create-namespace set to false into non-existent namespace — verifies the install fails gracefully and release-revision is empty
• All existing install/upgrade tests continue to pass (backward-compatible: create-namespace defaults to true)