Refactor message sending to host in `zRollupBuildInWorker

[iNewLegend]

Title: Refactor message sending to host in zRollupBuildInWorker

Description:
The current implementation in zRollupBuildInWorker sends a formatted message to the host, which is not considered best practice. This needs to be refactored to improve code quality and maintainability.

File:
packages/zenflux-cli/src/core/build.ts

Current Code:

// TODO: Sending formated message to the host, not the best practice.
host.sendMessage("message", "build", "prepare", config.outputName);

Suggested Improvement:

• Refactor the code to use a more appropriate method for sending messages to the host.
• Consider using sendVerbose or sendMessage with a different approach that does not involve passing formatted messages directly.

Additional Context:
This change is aimed at improving the clarity and maintainability of the code. The current approach of sending formatted messages directly is not ideal and should be revised.

Feel free to adjust the issue details as needed!

Originally posted by @codiumai-pr-agent-pro[bot] in #35 (comment)