Untangle config inheritance (#41541)
* remove from base
* delete
* fetcher fix
* missing values
* update
* is decoder missing
* forgot to add
* add special tokens with default `None` in text models
* fsmt has unused subconfig, fix it!
* update
* fix
* add missig token id defaults
* fix more tests
* tie_word_embeddings
* tiny fixes
* more test fixes
* fix docstrings
* fix copies
* fix style?
* fix copied again
* fix copies
* fix examples
* delete left over print stmt
* splitnter
* this defi will fix a bunch decoder-only models
* make style
* fix copies
* not all models are supposed to have an attr for `tie_word_embeddings`!
* comment out
* fix
* more fixes
* fix copies
* docstring and non-model tests
* update
* fix repo consistency
* style
* fix
* revert
* remove unused attr
* fix repo
* fix test
* fix a few tests, more tests
* fix gemma & llava
* style
* gemma3n also
* new models as well
* skip the test
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Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>
