Added configuration options for the new PreembeddingEmbedder.

- Added `preembedding_embedder` config dictionary in `config`
- Added `preemb_dim_size` property in `config` for specifying single seq embedding size.

openfold/config.py

@@ -189,6 +189,7 @@ c_m = mlc.FieldReference(256, field_type=int)
 c_t = mlc.FieldReference(64, field_type=int)
 c_e = mlc.FieldReference(64, field_type=int)
 c_s = mlc.FieldReference(384, field_type=int)
+preemb_dim_size = mlc.FieldReference(1280, field_type=int)
 blocks_per_ckpt = mlc.FieldReference(None, field_type=int)
 chunk_size = mlc.FieldReference(4, field_type=int)
 aux_distogram_bins = mlc.FieldReference(64, field_type=int)
@@ -403,6 +404,13 @@ config = mlc.ConfigDict(
                 "c_m": c_m,
                 "relpos_k": 32,
             },
+            "preembedding_embedder": {
+                "tf_dim": 22,
+                "preembedding_dim": preemb_dim_size,
+                "c_z": c_z,
+                "c_m": c_m,
+                "relpos_k": 32,
+            },
             "recycling_embedder": {
                 "c_z": c_z,
                 "c_m": c_m,