Lock the Matrix View By, collapse single assignments, custom Find Resource row labels

Three enhancements across the core components:

• Lock the Matrix View By mode – A new Lightning App Builder property lets admins lock the Matrix component “View By” selector. When locked, the picklist appears disabled with a label explaining the locked state, rather than being hidden.
• Collapse single assignments by default – A new user preference collapses single-assignment rows by default in Enhanced Time Tracking for a cleaner view.
• Customize the Find Resource row header – A new admin property, Resource Row Label Field, lets you choose which Resource field appears as the first column heading for each row in Find Resource results. Defaults to Name; point it at a text formula field to combine values, for example Name and Team.