Add docs for key rotation

[SimiHunjan]

Problem

Create and publish documentation on key rotation in Hedera.

Acceptance Criteria

• Include the following sections in the content:
• What is key rotation?
• Why is key rotation important?
• When should key rotation be performed?
• Who is responsible for key rotation?
• Where does key rotation apply in Hedera (e.g., accounts, smart contracts)?
• How to perform key rotation in Hedera?
• Pros and cons of key rotation
• Include examples where applicable

Solution

Create and publish content

Alternatives

No response