Refactor termination and rental object entities

- Removed the "Kündigungen" field from the German and English rental object JSON files.
- Updated the termination JSON files to reflect new field names and structure, including renaming "kuendigungsart" to "beendigungsTatbestand" and "kuendigungsgrund" to "kuendigungsgrund" with updated options.
- Deleted the old "CKuendigung" entity definition and related metadata, consolidating functionality into "CKndigung".
- Adjusted the service logic to accommodate the new structure, ensuring proper linking of landlords and tenants.
- Updated dynamic visibility logic for fields based on conditions related to termination reasons and delivery methods.
- Cleaned up metadata definitions for both termination and rental object entities, removing unnecessary relationships and fields.
- Incremented cache and microtime values in the configuration file.

custom/Espo/Custom/Resources/i18n/en_US/CMietobjekt.json

@@ -20,7 +20,6 @@
         "contact2mietobjekt": "Contacts",
         "vmhRumungsklages": "Eviction Lawsuits",
         "mietinkassos": "Rent Collection",
-        "kndigungen": "Terminations",
         "contactsMietobjekt": "Portal Users",
         "dokumentesMietobjekt": "Documents"
     },