Reject NaN/Infinity in JS arguments to avoid silent conversion

[bbopen]

Summary

JSON.stringify silently converts NaN, Infinity, and -Infinity to null in arrays/objects. This causes silent data corruption when passing numeric arguments into the bridge.

Failure mode

• Call bridge.call('math', 'sqrt', [NaN]).
• Payload JSON contains null instead of NaN.
• Python receives None and executes with unexpected values.

Evidence

• src/runtime/node.ts send() uses JSON.stringify(message) directly.
• JSON.stringify converts non-finite numbers to null.

Proposed fix

• Validate arguments/kwargs for non-finite numbers before serialization and throw a clear BridgeProtocolError.
• Optionally add a strict mode that rejects unsupported JS types (functions, symbols, undefined).

Acceptance criteria

• Passing NaN/Infinity in args or kwargs throws a clear error and does not silently convert.
• Add tests covering NaN/Infinity in both args and kwargs.

[bbopen]

Fixed in PR #153: SafeCodec validates special floats by default (rejectSpecialFloats: true). The containsSpecialFloat() validator recursively checks for NaN/Infinity in arguments before encoding.