PatronTransaction: facets & serialization

[zannkukai]

• Adds facet configuration for PatronTransactionEvent resource.
• Simplifies default_facet_factory method.
• Generalizes nested aggregations serialization.

Co-Authored-by: Renaud Michotte renaud.michotte@gmail.com

[ManaDeweerdt]

• : MD(12.01): wrong menu name for 'Inventory list'.

• REP: [acceptance criteria] There is no sort options for the list.

• REP: [acceptance criteria] The list is not filtered by today's date by default.

• REP: The translations for categories and types are unclear ("en retard" should be "frais de retard").

• REP: It is unclear what the difference is between category and subtype, why do we need these two separated facets ?

• REP: [acceptance criteria] There is no fee detailed view. --> MD: US would cost more. Not blocking.

• BER: [not blocking but boring] In the CSV, the amount is displayed with a dot "2.0" (in place of "2,0"). The Spreadsheet doesn't consider it as a number but as TEXT. So, the staff can't sum the total amount of fees in the table. (An option to change on Spreadsheet side perhaps ?)
  - MD (2/12) still the case.
  Ex LibreOffice
  
  Ex Excel :
  

• MD: library name not well displayed when there is no result --> not linked to the pr. Issue to create
  

• REP: UX: Contrast should be higher between text and background in brief view info badges (librarian, library, type). Could also be better in the fees summary facet.