[Docs] Enhance Design Reviews Page with Suggested Best Practices for Using Comments

[zihanKuang]

Description:
Update the Design Reviews documentation page to include suggested best practices for fully utilizing the Comments feature. These practices should help users better organize and contextualize their design feedback. Specifically, include the following:

• Use of color-coded comments to distinguish topical categories (e.g., red for Security, blue for Scaling).
• Use of annotation arrows to clearly link each comment to the relevant design area.
• Instruction on how to lock comments in-place for persistent visibility during reviews.
• Use of the Group feature to bundle related comments with their corresponding components.
• ...