Fix inconsistent KafkaSQL SSL security property naming

[EricWittmann]

Summary

This PR addresses the inconsistent naming of KafkaSQL SSL security configuration properties by introducing new properties with the consistent apicurio.kafkasql.security.ssl.* prefix while maintaining full backward compatibility.

• Added new properties with consistent .security prefix for all SSL configuration
• Deprecated old apicurio.kafkasql.ssl.* properties with @Deprecated annotations
• Implemented fallback logic to support both old and new property names seamlessly
• Added runtime warnings when deprecated properties are used, directing users to migrate
• Updated documentation to reflect new properties and mark deprecated ones

Related Issue

Fixes #6398

Changes Made

Configuration Properties (KafkaSqlConfiguration.java)

New Properties (consistent naming):

• apicurio.kafkasql.security.ssl.truststore.password
• apicurio.kafkasql.security.ssl.keystore.location
• apicurio.kafkasql.security.ssl.keystore.type
• apicurio.kafkasql.security.ssl.keystore.password
• apicurio.kafkasql.security.ssl.key.password

Deprecated Properties (still functional):

• apicurio.kafkasql.ssl.truststore.password → use apicurio.kafkasql.security.ssl.truststore.password
• apicurio.kafkasql.ssl.keystore.location → use apicurio.kafkasql.security.ssl.keystore.location
• apicurio.kafkasql.ssl.keystore.type → use apicurio.kafkasql.security.ssl.keystore.type
• apicurio.kafkasql.ssl.keystore.password → use apicurio.kafkasql.security.ssl.keystore.password
• apicurio.kafkasql.ssl.key.password → use apicurio.kafkasql.security.ssl.key.password

Implementation Details

1. Backward Compatibility: The tryToConfigureClientSecurity() method uses Optional.or() to prefer new property names while falling back to deprecated ones if needed
2. User Warnings: Added SLF4J logging to warn users when deprecated properties are detected, with clear migration guidance
3. Documentation: Updated ref-registry-all-configs.adoc to include new properties and mark deprecated ones

Migration Guide

Users currently using the deprecated properties should update their configurations:

Old Property (Deprecated)	New Property (Recommended)
apicurio.kafkasql.ssl.truststore.password	apicurio.kafkasql.security.ssl.truststore.password
apicurio.kafkasql.ssl.keystore.location	apicurio.kafkasql.security.ssl.keystore.location
apicurio.kafkasql.ssl.keystore.type	apicurio.kafkasql.security.ssl.keystore.type
apicurio.kafkasql.ssl.keystore.password	apicurio.kafkasql.security.ssl.keystore.password
apicurio.kafkasql.ssl.key.password	apicurio.kafkasql.security.ssl.key.password

Note: Old properties continue to work but will be removed in a future major version.

Test Plan

• Verify that new properties work correctly with SSL/TLS configuration
• Verify that deprecated properties still work (backward compatibility)
• Verify that fallback logic prefers new properties over deprecated ones
• Verify that deprecation warnings are logged when old properties are used
• Verify that no warnings are logged when new properties are used
• Review documentation updates for accuracy