Unselect All Option for Rule Discovery Template Selection

When installing rules through Rule Discovery, users must manually unselect each rule individually if they only want to install a subset, such as vendor-specific rules. This enhancement would add an 'Unselect All' or 'Clear Selection' action to the Config Rule Template selection interface, allowing the full list to be cleared in a single action before filtering and selecting the desired rules. Customers installing targeted rule subsets would benefit from a faster, less error-prone selection workflow.