[IMP] analytic: add search more option

Allow users to find analytic accounts in the analytic widget if there are more than 7 results for their search criteria, by providing a Search More option.

Additional Enhancements include:
- remove the 'Add a Line' button. replace with an empty tag (no analytic account, remainder of distribution)
- remove the custom AutoComplete. this was used to set the active group on autoComplete focus, and to prevent propogation of click events.
- no longer keep track of the active group (editing plan). Instead pass the group (plan id) to the relevant functions.
- rename variables, for example request > searchTerm
- keep the header of the popup in place (no scroll when there are many tags)
- test the widget in list view (with the search more feature)
- add a new analytic account list view, as users should not multi-edit in the search more dialog

Current behavior before PR:
Users were forced to type the entire analytic account name if they had many analytic accounts with similar names.

Desired behavior after PR is merged:
A "Search More" option is added to the Autocomplete options when there are more than 6 analytic accounts found. The Search More option provides a SelectCreate Dialog where users are able to find the required analytic account easily. Users are able to select multiple accounts by checking the items in the list.

Task-3180055

Part-of: odoo/odoo#115504