Enhance PR validation and Slack integration for new idea notifications

[tres-caras]

Title: Enhance PR validation and Slack integration for new idea notifications

Description:

Currently, when a PR is created, two jobs are executed to validate that only one file is added and to notify the new idea in a GitHub channel. The attached screenshot demonstrates the current notification process.

I propose that we enhance this workflow by incorporating additional features, such as:

1. Differentiate the flow for merged PRs: Currently, the validation and notification process happens when a PR is created. We can improve the workflow by having a separate flow for merged PRs, which could include additional checks or notifications.

2. Integrate Slack message interactions: It would be great to have more interactive Slack notifications when a new idea is added. This could include features like likes, emojis, and other interactive elements that encourage team members to engage with the new idea and provide feedback.

These enhancements will not only streamline the PR validation and notification process but also foster a more collaborative and engaging environment for team members to share and discuss new ideas.