Retether Keras 3.7.0

[t-kalinowski]

New functions:

• activation_celu()
• activation_glu()
• activation_hard_shrink()
• activation_hard_tanh()
• activation_log_sigmoid()
• activation_soft_shrink()
• activation_squareplus()
• activation_tanh_shrink()
• config_disable_flash_attention()
• config_enable_flash_attention()
• config_is_flash_attention_enabled()
• initializer_stft()
• layer_max_num_bounding_boxes()
• layer_stft_spectrogram()
• loss_circle()
• metric_concordance_correlation()
• metric_pearson_correlation()
• op_celu()
• op_exp2()
• op_glu()
• op_hard_shrink()
• op_hard_tanh()
• op_ifft2()
• op_inner()
• op_soft_shrink()
• op_squareplus()
• op_tanh_shrink()

New arguments:

• callback_backup_and_restore(): Added double_checkpoint argument to save a fallback checkpoint
• callback_tensorboard(): Added support for profile_batch argument
• layer_group_query_attention(): Added flash_attention and seed arguments
• layer_multi_head_attention(): Added flash_attention argument
• metric_sparse_top_k_categorical_accuracy(): Added from_sorted_ids argument

Performance improvements:

• Added native Flash Attention support for GPU (via cuDNN) and TPU (via Pallas kernel) in JAX backend
• Added opt-in native Flash Attention support for GPU in PyTorch backend
• Enabled additional kernel fusion via bias_add in TensorFlow backend
• Added support for Intel XPU devices in PyTorch backend

Documentation improvements and bug fixes.