Add permissions checks on configuration pages and etc

[callmevladik]

In order to enhance the user experience and enforce permission levels within the application, certain UI elements need to be disabled for users with the developer role. The following UI elements should be disabled based on the user's permissions:

1. {}Add a link button on the Overview page.{}

2. {}Add integration button on the Configuration page.{}

3. {}Add button on the first component or environment page.{}

This task involves both front-end changes to conditionally render these elements based on the user's role and back-end changes to ensure that the permissions are correctly enforced.

{}Acceptance Criteria:{}

1. Users with the developer role do not see the 'Add a link' button on the Overview page.
2. Users with the developer role do not see the 'Add integration' button on the Configuration page.
3. Users with the developer role do not see the 'Add' button on the first component or environment page.
4. Attempting to access these functionalities directly (e.g., via URL manipulation) by a user with the developer role results in an appropriate access denied message.
5. Documentation is updated to reflect these UI and permission changes.