fix: Stateless mcp server registration tools failed

[YunKuiLu]

• Fix StatelessServerSpecificationFactoryAutoConfiguration.toolSpecs method signature to use McpStatelessServerFeatures.SyncToolSpecification
• Add StatelessServerSpecificationFactoryAutoConfiguration to spring imports
• Update McpStatelessServerAutoConfigurationIT and McpServerAutoConfigurationIT

This PR fixes Stateless mcp server registration tools failed.

Steps to reproduce

1. clone https://github.com/YunKuiLu/spring-ai-issue-4396
2. run SpringAiIssue4396Application.java
3. execute

curl --location --request POST 'http://127.0.0.1:8080/mcp' \ 
--header 'Accept: application/json,text/event-stream' \
--header 'Content-Type: application/json' \
--data-raw '{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/list",
  "params": {
  }
}'

Then you will get:

{"jsonrpc":"2.0","id":1,"result":{"tools":[]}}

The expected output is

{"jsonrpc":"2.0","id":1,"result":{"tools":[{"name":"getCurrentTime","title":"getCurrentTime","description":"","inputSchema":{"type":"object","properties":{},"required":[]},"annotations":{"title":"","readOnlyHint":false,"destructiveHint":true,"idempotentHint":false,"openWorldHint":true}}]}}

[YunKuiLu]

I want to add more unit tests

[tzolov]

Nice catch @YunKuiLu Thanks you!

Rebased, additional changes applied, squashed and merged at 1b3705f

[AnirudhaDesai]

Do we have an ETA on when this commit will be released? I am in need of this fix asap for a project.