SSE endpoints not connecting

[rhvall]

Describe the bug
Using the latest main code 0.9.0 (commit 7a76001) I tried to connect to multiple "SSE" MCP endpoints but there was a problem

To Reproduce

import Foundation
import MCP

// Initialize the client
let mcpList = [
    "https://mcp.deepwiki.com/sse",
    "https://mcp.deepwiki.com/mcp",
    "https://mcp.semgrep.ai/sse",
    "https://remote.mcpservers.org/sequentialthinking/mcp"
]

let connectTest = { (transport: Transport) async -> Bool in

    do {
        let client = Client(name: "MyApp", version: "1.0.0")
        let result = try await client.connect(transport: transport)

        // Check server capabilities
        print(result.capabilities)
        await client.disconnect()
        return true
    } catch {
        return false
    }
}

for link in mcpList {
    let url = URL(string: link)!

    // Create a transport and connect
    let transport = HTTPClientTransport(
        endpoint: url,
        streaming: true
    )

    let res = await connectTest(transport)
    print("HTTP URL: \(link). Result: \(res)")
}

Expected behavior
The client should connect to the SSE MCP server. But it only does with those that end with "/mcp". I tried with "streaming=true/false" but it did not make any change.

The problem is that not every MCP server offers "/mcp", multiple are only "/sse". From this list:
https://mcpservers.org/remote-mcp-servers
Most of them are using "sse" at the end.

Logs
This is the output of the example code above:

HTTP URL: https://mcp.deepwiki.com/sse. Result: false
Capabilities(logging: nil, prompts: nil, resources: nil, sampling: nil, tools: Optional(MCP.Server.Capabilities.Tools(listChanged: Optional(true))))
HTTP URL: https://mcp.deepwiki.com/mcp. Result: true
HTTP URL: https://mcp.semgrep.ai/sse. Result: false
Capabilities(logging: nil, prompts: nil, resources: nil, sampling: nil, tools: Optional(MCP.Server.Capabilities.Tools(listChanged: nil)))
HTTP URL: https://remote.mcpservers.org/sequentialthinking/mcp. Result: true

Additional context
I used as well the branch here: "#101" (commit 5978c71), but it did not work as well changing to "SSEClientTransport"