feat: support MCP tools and enhance resource updating with renaming c…

[cin-niko]

Description

Added native support for MCP (Model Context Protocol) tools inside kotaemon, making them seamlessly usable by the underlying ReAct and ReWOO reasoning agents (request #780).

• Users can now connect, view, and manage any standard external MCP servers directly from the new MCP Servers tab inside the Resources page.
  • Bulk Operations: Supports creating multiple MCP servers at once using the "mcpServers" JSON structure.
  • Tool Discovery: Asynchronously pulls and displays available capabilities dynamically fetched from the connected MCP endpoints (supports both stdio and sse transports).
• Enhanced Resource Management: Support renaming capabilities across the Resource components (LLMs, Embeddings, Rerankings, etc.).

Type of change

• New features (non-breaking change).
• Bug fix (non-breaking change).
• Breaking change (fix or feature that would cause existing functionality not to work as expected).

Checklist

• I have performed a self-review of my code.
• I have added thorough tests if it is a core feature.
• There is a reference to the original bug report and related work.
• I have commented on my code, particularly in hard-to-understand areas.
• The feature is well documented.

[phv2312]

Unit test fails, please check @cin-niko

[cin-niko]

I've fixed the unit tests, pls help review @phv2312