model : add Jina Embeddings v5 Nano (partial EuroBERT) support (#19826)

* WIP: Add EuroBERT support with autoformatting changes

This commit includes:
- EuroBERT model implementation for GGUF conversion
- C++ backend support for EuroBERT architecture
- Unintended autoformatting changes to Python files

Saving before reverting formatting-only changes.

* feat: add back eos assert when not last token pooling

* feat: removed duplicated code and cleanup

* feat: removed not working architectures and unnecessary check

* fix: typo

* fix: dynamic pooling config

* feat: added an example model for eurobert

* feat: proper llama-vocab implementation for jina-v5

* fix: removed unnecessary comments

tests/test-tokenizer-0.sh

@@ -13,7 +13,12 @@ fi
 name=$1
 input=$2
 
-make -j tests/test-tokenizer-0
+# Build using CMake if binary doesn't exist
+if [ ! -f ./build/bin/test-tokenizer-0 ]; then
+    printf "Building test-tokenizer-0 with CMake...\n"
+    cmake -B build -DLLAMA_BUILD_TESTS=ON
+    cmake --build build --target test-tokenizer-0 -j
+fi
 
 printf "Testing %s on %s ...\n" $name $input
 
@@ -23,7 +28,7 @@ printf "Tokenizing using (py)  Python AutoTokenizer ...\n"
 python3 ./tests/test-tokenizer-0.py ./models/tokenizers/$name --fname-tok $input > /tmp/test-tokenizer-0-$name-py.log 2>&1
 
 printf "Tokenizing using (cpp) llama.cpp ...\n"
-./tests/test-tokenizer-0 ./models/ggml-vocab-$name.gguf $input > /tmp/test-tokenizer-0-$name-cpp.log 2>&1
+./build/bin/test-tokenizer-0 ./models/ggml-vocab-$name.gguf $input > /tmp/test-tokenizer-0-$name-cpp.log 2>&1
 
 cat /tmp/test-tokenizer-0-$name-py.log | grep "tokenized in"
 cat /tmp/test-tokenizer-0-$name-cpp.log | grep "tokenized in"