enhc: Code Refactoring, Project Restructuring, and Unified Stylings

[Spiral-Memory]

Brief Title

Acceptance Criteria Fulfillment

• [x] Removed Module.css files.
• [x] Added inline stylings with Emotion CSS.
• [x] Removed hotfix and added actual fix for emoji alignment.
• [x] Removed older grid component (non-functional).
• [x] Added a new grid component without any Module.css files.
• [x] Fixed modal stylings.
• [x] Refactored search component into sidebar.
• [x] Refactored Attachment Component (It was using unnecessary code instead of using the component modal).
• [x] Added styles.js files for components exceeding 2 lines of CSS.
• [x] Changed <div> and <span> to <Box>.
• [x] Basic project restructuring: separated core components from views.

Fixes #575

Video/Screenshots

A video demonstrating that all major features are working properly after these changes.

https://github.com/RocketChat/EmbeddedChat/assets/78961432/00298d41-94d2-40f8-af3d-6d1ae36d28c0

[Spiral-Memory]

Hey @sidmohanty11 , I've made some changes related to refactoring many components' code and unifying the stylings, and I've done a simple restructuring of the project, separating components and views.

As far as I have tested, I'm seeing things working fine. However, since this PR has a lot of changes, there is a high chance of introducing bugs into the project, which I'll correct as soon as I notice them. Hence, I suggest creating a new branch 'v0.2' for the changes up to this point to preserve the project. Without that, it's unsafe to merge. Once you create a new branch, please review and merge it to 'develop' branch, and I'll fix any arising issues. Also, please don't squash and commit for this PR; otherwise, it will become difficult to go back to certain changes and drop or revert them.