feat: add a primitive form of continuous batching (#2167)

* feat: add a primitive form of continuous batching

* fix: deadlock in batching fallback

* fix: windows build

* chore: suppress the contbatch arg from --help

* feat: batch-aware rep_pen_slope

* fix: automatically disable shifting when batching is enabled

* fix: mixed-path state corruption

* fix: attempt to fully separate the two pipelines

* added a semaphore to prevent non-batchable requests from starting while batched requests are running

---------

Co-authored-by: Concedo <39025047+LostRuins@users.noreply.github.com>

expose.cpp

@@ -258,6 +258,33 @@ extern "C"
     bool has_finished() {
         return generation_finished;
     }
+    bool batch_generate_enabled() {
+        return gpttype_batch_generate_enabled();
+    }
+    int batch_generate_submit(const generation_inputs inputs) {
+        return gpttype_batch_generate_submit(inputs);
+    }
+    bool batch_generate_has_finished(int request_id) {
+        return gpttype_batch_generate_has_finished(request_id);
+    }
+    int batch_generate_stream_count(int request_id) {
+        return gpttype_batch_generate_stream_count(request_id);
+    }
+    const char * batch_generate_new_token(int request_id, int idx) {
+        return gpttype_batch_generate_new_token(request_id, idx);
+    }
+    const char * batch_generate_pending_output(int request_id) {
+        return gpttype_batch_generate_pending_output(request_id);
+    }
+    generation_outputs batch_generate_result(int request_id) {
+        return gpttype_batch_generate_result(request_id);
+    }
+    bool batch_generate_abort(int request_id) {
+        return gpttype_batch_generate_abort(request_id);
+    }
+    void batch_generate_release(int request_id) {
+        gpttype_batch_generate_release(request_id);
+    }
     bool has_audio_support()
     {
         return audio_multimodal_supported;