Add MCP proxy address config support, better error messages, redesigned Config panel

[pulkitsharma07]

1. Add support to connect to MCP Inspector Proxy running on a different address (host/port).

2. Better error messaging in case MCP Server is down OR MCP Inspector Proxy is down.

3. Redesigned configuration panel to show key names (which will help in moving to a centralised config file in the future), with tooltips

Screen.Recording.2025-04-01.at.7.31.14.PM.mov

Motivation and Context

• Removes need of setting proxy address via url params (Support overriding proxy server url #165)
• Can also help with debugging case like How to run this tool and use it when my MCP server is a remote server? #219

How Has This Been Tested?

Tested locally with remote MCP + running MCP proxy on different port

Breaking Changes

None

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

[pulkitsharma07]

cc @cliffhall @olaservo for review

[cliffhall]

LGTM! 👍

• Reviewed the PR and tested locally with valid and invalid proxy address.

• Tooltips also work (proxy one is a little long, but ok).

[cliffhall]

Reaching out to @olaservo to weigh in on the implementation and who might also be able to test on Windows.

[cliffhall]

@pulkitsharma07 looks like there are some conflicts to resolve.

[pulkitsharma07]

Resolved

[cliffhall]

@pulkitsharma07 yet again more conflicts to resolve.

[pulkitsharma07]

@cliffhall done

[cliffhall]

Tested again locally. LGTM! 👍