types: add context_length to ProcessResponse (#538)

Author: ParthSareen

examples/ps.py

@@ -23,4 +23,5 @@
   print('  Size: ', model.size)
   print('  Size vram: ', model.size_vram)
   print('  Details: ', model.details)
+  print('  Context length: ', model.context_length)
   print('\n')

ollama/_types.py

@@ -533,6 +533,7 @@ class Model(SubscriptableBaseModel):
     size: Optional[ByteSize] = None
     size_vram: Optional[ByteSize] = None
     details: Optional[ModelDetails] = None
+    context_length: Optional[int] = None
 
   models: Sequence[Model]