model : add support for JinaBertModel with non-gated ffn (#18475)

model : add support for JinaBertModel with non-gated ffn (#18475)

* WIP: Initial commit for fixing JinaBert original FF type support

* convert: add jina-v2-de tokenizer variant for German_Semantic_V3

* convert: fix token collision in BERT phantom vocab conversion

* convert: add feed_forward_type metadata

* model: add feed_forward_type metadata for jina-bert-v2

* model: jina-bert-v2 support standard GELU FFN variant

* model: remove ffn_type, detect FFN variant from tensor dimensions

* Update src/llama-model.cpp

Co-authored-by: Sigbjørn Skjæret <redacted>
* Update src/llama-model.cpp

Co-authored-by: Sigbjørn Skjæret <redacted>
* Update src/models/bert.cpp

Co-authored-by: Sigbjørn Skjæret <redacted>
* Update src/models/bert.cpp

Co-authored-by: Sigbjørn Skjæret <redacted>
* revert collision fix to be handled in separate PR

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Co-authored-by: Sigbjørn Skjæret <redacted>