Adopt result-style error handling for factory functions instead of exceptions

[coderabbitai]

Background

During PR review #80, @LinZhihao-723 suggested adopting result-style error handling (similar to Rust's Result type) instead of relying on exceptions, particularly for factory functions. The current approach of using factory functions that throw exceptions is not meaningful since constructors can behave similarly.

Benefits

Result-style error handling would allow:

• Forwarding error codes from the core FFI layer more effectively
• More explicit error handling patterns
• Better integration with the underlying CLP core error handling

Challenges

The main challenge identified is mapping such result types to Emscripten's Embind system for JavaScript bindings.

Timing

This enhancement should be implemented after:

1. Syncing the latest CLP code into clp-ffi-js
2. Completion of the proposed error handling refactoring in the CLP codebase

References

• Original discussion: feat: Add support for retrieving CLP IR stream-level metadata from IR stream readers (resolves #77). #80 (comment)
• PR: feat: Add support for retrieving CLP IR stream-level metadata from IR stream readers (resolves #77). #80

Requested by: @junhaoliao