api!: remove verification methods from the FFI and JSON-RPC APIs

Core no longer tracks verification, so the API has nothing left
to report and UIs should drop their checkmark and "Introduced by" code.

BREAKING CHANGE: dc_contact_is_verified() and dc_contact_get_verifier_id() are removed.

BREAKING CHANGE: the JSON-RPC Contact object loses the `isVerified` and `verifierId` fields. A bot reading `snapshot.is_verified` now gets an `AttributeError` at runtime.

BREAKING CHANGE: the Python bindings lose `Contact.is_verified()` and `Contact.get_verifier()`.

BREAKING CHANGE: DC_STR_CONTACT_VERIFIED (35) is removed, so UIs should stop registering a translation for it. A stock id core does not know is logged and otherwise ignored, so an un-updated client keeps working.

python/src/deltachat/contact.py

@@ -71,17 +71,6 @@ class Contact:
         """Unblock this contact. Messages from this contact will be retrieved (again)."""
         return lib.dc_block_contact(self.account._dc_context, self.id, False)
 
-    def is_verified(self) -> bool:
-        """Return True if the contact is verified."""
-        return lib.dc_contact_is_verified(self._dc_contact) == 2
-
-    def get_verifier(self, contact) -> Optional["Contact"]:
-        """Return the address of the contact that verified the contact."""
-        verifier_id = lib.dc_contact_get_verifier_id(contact._dc_contact)
-        if verifier_id == 0:
-            return None
-        return Contact(self.account, verifier_id)
-
     def get_profile_image(self) -> Optional[str]:
         """Get contact profile image.
 

python/tests/test_3_offline.py

@@ -115,7 +115,6 @@ class TestOfflineContact:
         assert contact1.addr == "some1@example.org"
         assert contact1.display_name == "some1"
         assert not contact1.is_blocked()
-        assert not contact1.is_verified()
 
     def test_get_blocked(self, acfactory):
         ac1 = acfactory.get_pseudo_configured_account()