Support customized headers for SSE based MCP Client

[QZero233]

Expected Behavior

Allow us to add customized headers such as Authorization when using SSE based MCP Client.
As some MCP Server providers only support add api-key in headers (Like alibaba)

Current Behavior

Currently, only url and sse-endpoint are supported for sse based mcp client.

spring-ai/auto-configurations/mcp/spring-ai-autoconfigure-mcp-client-common/src/main/java/org/springframework/ai/mcp/client/common/autoconfigure/properties/McpSseClientProperties.java

Line 86 in bd1834d

public record SseParameters(String url, String sseEndpoint) {

[quaff]

It's duplicate of #3949.

[QZero233]

Sorry for this duplicated issue, thank you so much for awaring me about this PR！