fix: avoid infinite recursion

[wzxxing]

Summary

Previously, the _connect method retries on RuntimeError. This can cause infinite recursion if

1. the network is down
2. there were legit McpError that terminate the session.

This fix ensures that

1. when a RuntimeError wraps an McpError, the underlying McpError is properly extracted and raised (user does not have the permission to InvokeMcp)
2. connection retries only on TimeoutException for at most 3 times.

Changes

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User experience

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Checklist

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• I have reviewed the contributing guidelines
• I have performed a self-review of this change
• Changes have been tested
• Changes are documented

Is this a breaking change? (Y/N)

• Yes
• No

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• Did integration tests succeed?
• If the feature is a new use case, is it necessary to add a new integration test case?

Acknowledgment

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