feat(context): add metadata to switch_context method

Include metadata parameter in the switch_context method to
preserve metadata when switching contexts.

refactor(user_endpoint): update auth_router tags

Remove "user" tag from auth_router post methods and clean up
commented-out logger code.

Author: atompie

tracardi/context.py

@@ -65,12 +65,14 @@ def is_production(self) -> bool:
     def context_abrv(self) -> str:
         return 'p' if self.production else 't'
 
-    def switch_context(self, production, user=None, tenant=None) -> 'Context':
+    def switch_context(self, production, user=None, tenant=None, metadata=None) -> 'Context':
         if user is None:
             user = self.user
         if tenant is None:
             tenant = self.tenant
-        return Context(production=production, user=user, tenant=tenant)
+        if metadata is None:
+            metadata = self.metadata
+        return Context(production=production, user=user, tenant=tenant, metadata=metadata)
 
     def get_user_less_context_copy(self) -> 'Context':
         return Context(