Add Xquik MCP discovery sample

[kriptoburak]

PR Type

• Add new sample
• Update existing sample
• Add new test cases
• Fix test failures
• Documentation/Configuration update

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Description

Closes #125.

Adds functionality/xquik_mcp_discovery, a small read-only AgentScope sample for exploring X / Twitter API routes through Xquik remote MCP server. It uses MCPClient and HttpMCPConfig, enables only the explore tool, searches current endpoint metadata, and requires no model-provider credentials.

The MCP origin is fixed to https://xquik.com/mcp. The bearer key cannot be redirected to an environment-configured host. Six offline tests cover that boundary, the read-only tool allow-list, API-key handling, default and explicit queries, JavaScript string escaping, result limits, and output conversion.

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Testing Validation

1. pre-commit run --all-files passed every repository hook, including mypy, Black, Flake8, Pylint, ESLint, Stylelint, and Prettier.
2. python -m unittest -v functionality.xquik_mcp_discovery.test_main passed 6 offline tests.
3. python -m py_compile passed for the package, sample, and tests.
4. uv pip check passed with AgentScope 2.0.6 on Python 3.11.
5. The current public MCP discovery document returned HTTP 200 and identifies https://xquik.com/mcp as the streamable HTTP endpoint. The endpoint returned 401 without authentication, as expected.

A live tool call was not run because it requires an Xquik API key. The tests make no network requests.

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Checklist

• All sample code has been formatted with pre-commit run --all-files.
• All new tests pass.
• Test coverage has not decreased.
• Sample code follows AgentScope configuration and MCP patterns.
• The root and sample documentation are updated.
• The sample installs independently through its requirements.txt.

Security and Independence

• Only the read-only explore tool is enabled.
• The sample never calls the live xquik execution tool.
• The fixed HTTPS origin prevents bearer-key forwarding to a configurable host.
• Xquik is an independent third-party service. Not affiliated with X Corp. "Twitter" and "X" are trademarks of X Corp.

Codex assisted with the current validation and repair. I reviewed the final implementation and test evidence.

[CLAassistant]

All committers have signed the CLA.