llama-context : report graph inputs and input tensors during sched reserve
- fix the tg (token generation) graph bs label to use n_seqs instead of a hardcoded 1
- report the number of graph inputs from llm_graph_result::inputs for both the pp and tg graphs
- report the number of input tensors (nodes and their src tensors flagged with GGML_TENSOR_FLAG_INPUT)
- log a warning when an input tensor has an op other than GGML_OP_NONE
- log a trace line for each input tensor and the nodes (name and op) that use it
Assisted-by: llama.cpp:DeepSeek-v4-Flash-0731