Forward logit_bias, logprobs, and n to llama.cpp backend

- Forward logit_bias and logprobs natively to llama.cpp
- Support n>1 completions with seed increment for diversity
- Fix logprobs returning empty dict when not requested

modules/llama_cpp_server.py

@@ -133,9 +133,20 @@ class LlamaServer:
 
             payload["samplers"] = filtered_samplers
 
+        logit_bias = []
         if state['custom_token_bans']:
-            to_ban = [[int(token_id), False] for token_id in state['custom_token_bans'].split(',')]
-            payload["logit_bias"] = to_ban
+            logit_bias.extend([[int(token_id), False] for token_id in state['custom_token_bans'].split(',')])
+
+        if state.get('logit_bias'):
+            for token_id_str, bias in state['logit_bias'].items():
+                logit_bias.append([int(token_id_str), bias])
+
+        if logit_bias:
+            payload["logit_bias"] = logit_bias
+
+        n_probs = state.get('logprobs', 0)
+        if n_probs and n_probs > 0:
+            payload["n_probs"] = n_probs
 
         return payload
 
@@ -215,6 +226,7 @@ class LlamaServer:
                 response.raise_for_status()  # Raise an exception for HTTP errors
 
             full_text = ""
+            self.last_completion_probabilities = []
 
             # Process the streaming response
             stop_event = state.get('stop_event')
@@ -240,6 +252,10 @@ class LlamaServer:
                         full_text += data['content']
                         yield full_text
 
+                    # Capture logprobs if present
+                    if 'completion_probabilities' in data:
+                        self.last_completion_probabilities.extend(data['completion_probabilities'])
+
                     # Check if generation is complete
                     if data.get('stop', False):
                         break