spec: add EAGLE3 speculative decoding support (#18039)

• llama : enable layer input extraction

• spec: support eagle3

• eagle3: fix params bug

• eagle3: support Gemma4 eagle3 from RedHatAI

• eagle3: set sync when get features from target

Co-authored-by: tnhnyzc [email protected]

• eagle3 : fix ubatch handling in embd_layer_inp extraction and encoder

Co-authored-by: Doğaç Eldenk [email protected]

• eagle3: adapt to upstream changes

• eagle3: fix rebase issues and adapt to upstream changes

• eagle3:exclude the eagle3 arch from test-llama-archs

• eagle3: fix editorconfig check failures

• eagle3: fix multi-seq issue in d2t vocab mapping

• cont : minor style / clean-up

• spec : remove common_speculative_setup_draft_model()

• llama : clean-up unused API

• eagle3: set d2t vocab mapping in decode graph

• cont : assert layer inputs are configured

• hparams : use n_embd_inp instead of n_embd_target_features

• eagle3: make output.weight optional and inherit from target model when needed

• haparams : generic norm-before-residual param

• llama-ext : consistent names

• cont : fix

• hparams : remove target_hidden_size

• cparams : rename output_layer_inp -> embeddings_layer_inp

• arch : reuse ATTN_NORM_2 instead of adding new hidden norm

• llama : clean-up names

• cont : add assert + comment

• Update conversion/llama.py

Co-authored-by: Sigbjørn Skjæret [email protected]

Co-authored-by: Georgi Gerganov [email protected] Co-authored-by: tnhnyzc [email protected] Co-authored-by: Doğaç Eldenk [email protected] Co-authored-by: Sigbjørn Skjæret [email protected]