Add read-only script execution

[won-seoop]

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This PR adds read-only script execution support so callers can explicitly execute scripts through EVAL_RO/EVALSHA_RO where supported.

Changes include:

• Add executeReadOnly(…) variants to RedisOperations and ScriptExecutor.
• Add evalReadOnly(…) and evalShaReadOnly(…) to Redis scripting command APIs, including string-friendly delegates.
• Route Lettuce and Jedis through their read-only scripting APIs.
• Register read-only script method aliases for command classification in connection splitting.
• Add unit coverage for script executor routing, command lookup aliases, and read-only connection splitting.

Closes #2617

Tests:

• ./mvnw -q -DskipITs -DskipDocker -Dtest=DefaultScriptExecutorUnitTests,RedisCommandUnitTests,RedisConnectionUtilsUnitTests test
• ./mvnw -q -DskipITs -DskipDocker -DskipTests compile test-compile
• ./mvnw -q -DskipITs -DskipDocker test fails locally because Redis is not running on 127.0.0.1:6379.