Refactor Policy Enforcer to Use Unified PolicyPaths

- Updated the Policy Enforcer to consolidate policy source configuration under a single `policyPaths` key, allowing for auto-detection of URLs, directories, and files.
- Removed deprecated keys such as `policyFile` and `policyUrls` from the configuration structure.
- Adjusted related code and tests to ensure compatibility with the new configuration format.
- Enhanced documentation to clarify the usage of `policyPaths` and provide examples for various configurations.

config/onix/adapter.yaml

@@ -51,6 +51,16 @@ modules:
         policyEnforcer:
           id: policyenforcer
           config:
+            # policyPaths: polymorphic, auto-detects each entry as URL, directory, or file
+            # Examples:
+            #   policyPaths: "./policies"                              # local directory
+            #   policyPaths: "https://example.com/compliance.rego"     # remote URL
+            #   policyPaths: "./policies/compliance.rego"              # local file
+            # For multiple sources, use YAML folded scalar (>-):
+            #   policyPaths: >-
+            #     https://example.com/compliance.rego,
+            #     https://example.com/safety.rego,
+            #     ./policies
             policyPaths: "./policies"
         signValidator:
           id: signvalidator