Update the docs for sharing in the cloud:
- Remove "C7 only" Tags on relevant documents
- Describe new API endpoints "share/enable" and "share/disable"
- Describe the behaviour when enabling/disabling sharing for existing shares
- Remove/Adjust part of CCSM documentation that says users shall deactivate it by environment variable
This ticket has two pull requests. Please also consider the PR in the cloud documentation that Jira doesn't pick up: https://github.com/camunda-cloud/camunda-cloud-documentation/pull/732