fix(mcp): reject non-finite or non-positive connect timeouts

[iqdoctor]

Summary

Validate /mcp connect --timeout values to reject non-finite and non-positive numbers.

Previously parse_connect_input accepted float(...) without finiteness checks, which allowed values like nan and inf.

Changes

• src/fast_agent/commands/handlers/mcp_runtime.py
  • After parsing timeout via float, require:
    • math.isfinite(timeout_seconds)
    • timeout_seconds > 0
  • Raise a clear ValueError when invalid.
• tests/unit/fast_agent/commands/test_mcp_runtime_handlers.py
  • Added parameterized coverage for nan, inf, -inf, 0, and -1.

Validation

• uv run pytest tests/unit/fast_agent/commands/test_mcp_runtime_handlers.py -q
• uv run ruff check src/fast_agent/commands/handlers/mcp_runtime.py tests/unit/fast_agent/commands/test_mcp_runtime_handlers.py

[evalstate]

LOL, you were quick on that one.