[CORE] Adding support for insertion of soft-tuned prompts (#4645)

Co-authored-by: Swapnil Parekh <swapnilp@ibm.com>
Co-authored-by: Joe G <joseph.granados@h2o.ai>
Co-authored-by: Antoni Baum <antoni.baum@protonmail.com>

vllm/adapter_commons/layers.py

@@ -0,0 +1,14 @@
+from dataclasses import dataclass
+from typing import Tuple
+
+
+@dataclass
+class AdapterMapping:
+    # Per every token in input_ids:
+    index_mapping: Tuple[int, ...]
+    # Per sampled token:
+    prompt_mapping: Tuple[int, ...]
+
+    def __post_init__(self):
+        self.index_mapping = tuple(self.index_mapping)
+        self.prompt_mapping = tuple(self.prompt_mapping)