GH-3426 Fix Spring AI Advisor documentation

[hyeonZIP]

Fixes GH-3426 (#3426)

• Fix outdated method names discovered while following documentation examples
• Remove references to unsupported methods in current version
• Update code examples to match current API implementation
• Additional corrections needed for deprecated methods in updated API

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[hyeonZIP]

deprecated methods in examples

in Logging Advisor

	@Override
	public Flux<AdvisedResponse> aroundStream(AdvisedRequest advisedRequest, StreamAroundAdvisorChain chain) {

		logger.debug("BEFORE: {}", advisedRequest);

		Flux<AdvisedResponse> advisedResponses = chain.nextAroundStream(advisedRequest);

        // aggregateAdvisedResponse() is deprecated
        return new MessageAggregator().aggregateAdvisedResponse(advisedResponses,
                    advisedResponse -> logger.debug("AFTER: {}", advisedResponse)); 
	}

Re-Reading (Re2) Advisor

public class ReReadingAdvisor implements CallAroundAdvisor, StreamAroundAdvisor {


	private AdvisedRequest before(AdvisedRequest advisedRequest) { 
               
                // advisedRequest.userParams() is deprecated
                // also, chatClientRequest.userParams() is not existing.
		Map<String, Object> advisedUserParams = new HashMap<>(advisedRequest.userParams());
		advisedUserParams.put("re2_input_query", advisedRequest.userText());

		return AdvisedRequest.from(advisedRequest)
			.userText("""
			    {re2_input_query}
			    Read the question again: {re2_input_query}
			    """)
			.userParams(advisedUserParams)
			.build();
	}

	@Override
	public AdvisedResponse aroundCall(AdvisedRequest advisedRequest, CallAroundAdvisorChain chain) { 
		return chain.nextAroundCall(this.before(advisedRequest));
	}

	@Override
	public Flux<AdvisedResponse> aroundStream(AdvisedRequest advisedRequest, StreamAroundAdvisorChain chain) { 
		return chain.nextAroundStream(this.before(advisedRequest));
	}

	@Override
	public int getOrder() { 
		return 0;
	}

    @Override
    public String getName() { 
		return this.getClass().getSimpleName();
	}
}

[dev-jonghoonpark]

There are two spaces between return and Mono.

[dev-jonghoonpark]

The indentation is incorrect.