Easy toggle of custom field Date Picker format (date vs date+time) from UI

Having to go change the database OR making a new custom field and migrating OR changing look and feel to hide/show if ok toggling them all seems silly.

customfield might have
com.atlassian.jira.plugin.system.customfieldtypes:datepicker
com.atlassian.jira.plugin.system.customfieldtypes:daterange

But customfieldvalue always has the time anyways:
YYYY-MM-DD 00:00:00
`DATEVALUE` datetime DEFAULT NULL,

You can adjust the database to:
com.atlassian.jira.plugin.system.customfieldtypes:datetime
com.atlassian.jira.plugin.system.customfieldtypes:datetimerange

Where in the UI would you go to change? Custom fields > edit > just beneath Search Template. Maybe call it Field Type Template.

Could be re-used later for other easy switches https://confluence.atlassian.com/display/JIRA/Changing+Custom+Field+Types

—

Speaking of which (probably need to make new tickets for it):

The Date Time Picker defaults to current time. (In some cases you might want to allow it to be set, but assume 00:00:00 if not manually set.

Like a 'Went Live Date' is probably the time you're in the ticket adjusting, but a 'Want Live Date' might be ok with just the day, and if you want more specific set the time.
com.atlassian.jira.plugin.system.customfieldtypes:datetime.autotime

Would be nice if the built-in Due Date system field would allow time (it's stored same way in jiraissue), but default to 00:00:00 and not shown in UI unless filled out as well.