contrib : rewrite AGENTS.md, make it more clear about project values (g…

…gml-org#21270)

* contrib : rewrite AGENTS.md, make it more clear about types of permitted AI usage

* permit AI for writing code

contrib: add "Requirements" section to PR template (ggml-org#20841)

* contrib: add "Requirements" section to PR template

* typo [no ci]

* use h2, add "Additional information"

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Co-authored-by: Piotr Wilkin (ilintar) <[email protected]>

tests : use `reasoning` instead of `reasoning_budget` in server tests (…

…ggml-org#20432)

vulkan: Replace deprecated VK_EXT_validation_features (ggml-org#17637)

* replaced deprecated VK_EXT_validation_features

* forgot to remove old code