clip : refactor clip_init, add tests (#12757)

clip : refactor clip_init, add tests (#12757)

* refactor clip_init

* fix loading file

* fix style

* test ok

* better test with report

* add missing headers

* clarify

* add KEY_MM_PATCH_MERGE_TYPE

* remove bool has_* pattern

* Apply suggestions from code review

Co-authored-by: Georgi Gerganov <redacted>
* Update examples/llava/clip.cpp

Co-authored-by: Georgi Gerganov <redacted>
* use ggml_soft_max_ext

* refactor logging system

* add minicpm-v-o 2.6 for testing

* use nullptr everywhere

* fix Yi-VL model

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Co-authored-by: Georgi Gerganov <redacted>