server : speculative checkpointing (#19493)

* server : speculative decoding using checkpoints

* server : fix draft check with checkpoints

* server : rename spec vars

* server : log levels

* server : refactored spec logic to speculative.cpp

* server : renamed spec checkpoints option

* server : fix spec checkpoints, logging

* speculative : checkpoints with draft model, logging

* server : n_tokens_cur and create_checkpoint in draft

* server : fix server_speculative_callback (slot.id)

* spec : fix ngram-map/begin idx_last_check

* spec : init ckpt (begin() wasn't called)

* chore: update webui build output

* server : restore sampler in spec checkpoint and clear mem

* cont : avoid --spec-use-checkpoints argument

* cont : remove server_prompt_checkpoint_with_size

* spec : rename (leave_draft_state)

* cont : clean-up

* cont : do not ignore partial drafts even if the are short

* cont : spec callback owned by session

* cont : simplify

* cont : avoid empty speculative session

* cont : simplify

* cont : simplify

* cont : enable mtmd speculative decoding

* cont : keep the spec sampler alive

* cont : simplify

* cont : fix nullptr deref + draft checkpoints

* cont : remove common_speculative_accept_response

* cont : remove callback

* cont : simplify

* cont : minor

* cont : simplify

* cont : fix accepted number

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Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

common/chat.cpp

@@ -2334,7 +2334,7 @@ common_chat_msg common_chat_peg_parse(const common_peg_arena &          src_pars
         ? input
         : params.generation_prompt + input;
 
-    LOG_DBG("Parsing PEG input with format %s: %s\n", common_chat_format_name(params.format), effective_input.c_str());
+    //LOG_DBG("Parsing PEG input with format %s: %s\n", common_chat_format_name(params.format), effective_input.c_str());
 
     common_peg_parse_flags flags = COMMON_PEG_PARSE_FLAG_LENIENT;
     if (params.debug) {