CUDA: add stream-based concurrency (llama/16991)

CUDA: add stream-based concurrency (llama/16991)

* CUDA: add stream-based concurrency

* HIP: fix hipStreamWaitEvent define and nodiscard warnings

* ggml-cuda: fix fusion inside stream

* ggml-cuda: fix bug w.r.t first stream launch

* ggml-cuda: format

* ggml-cuda: improve assert message

* ggml-cuda: use lambda instead of duplicating code

* ggml-cuda: add some more comments

* ggml-cuda: add more detailed comments about concurrency

* ggml-cuda: rename + remove unused var

* ggml-cuda: fix condition for stream launch

* ggml-cuda: address review comments, add destructor

* common.cuh: add is_valid for concurrent events

* common.cuh: make comment better

* update comment

Co-authored-by: Johannes Gäßler <redacted>
* update comment

Co-authored-by: Johannes Gäßler <redacted>
* common.cuh: fix lower_bound condition + remove join_node data from write_ranges

* ggml-cuda: fix overlap condition + shadowing parameter

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Co-authored-by: Carl Philipp Klemm <redacted>
Co-authored-by: Johannes Gäßler <redacted>