llama : move random seed generation to the samplers (#9398)

* llama_sampler_penalties : clamp penalty_last_n to zero

include/llama.h

@@ -1127,6 +1127,10 @@ extern "C" {
                              int32_t   n_logit_bias,
               const llama_logit_bias * logit_bias);
 
+
+    // Returns the seed used by the sampler if applicable, LLAMA_DEFAULT_SEED otherwise
+    LLAMA_API uint32_t llama_sampler_get_seed(const struct llama_sampler * smpl);
+
     /// @details Sample and accept a token from the idx-th output of the last evaluation
     //
     // Shorthand for: