mtmd: add gemma 4 test (vision + audio) [no ci] (ggml-org#21806)

* mtmd: add gemma 4 test (vision + audio)

* add to docs

Author: ngxson

docs/multimodal.md

@@ -94,6 +94,11 @@ NOTE: some models may require large context window, for example: `-c 8192`
 # Moondream2 20250414 version
 (tool_name) -hf ggml-org/moondream2-20250414-GGUF
 
+# Gemma 4
+(tool_name) -hf ggml-org/gemma-4-E2B-it-GGUF
+(tool_name) -hf ggml-org/gemma-4-E4B-it-GGUF
+(tool_name) -hf ggml-org/gemma-4-26B-A4B-it-GGUF
+(tool_name) -hf ggml-org/gemma-4-31B-it-GGUF
 ```
 
 **Audio models**:
@@ -118,6 +123,11 @@ NOTE: some models may require large context window, for example: `-c 8192`
 # Capabilities: audio input, vision input
 (tool_name) -hf ggml-org/Qwen2.5-Omni-3B-GGUF
 (tool_name) -hf ggml-org/Qwen2.5-Omni-7B-GGUF
+
+# Gemma 4
+# Capabilities: audio input, vision input
+(tool_name) -hf ggml-org/gemma-4-E2B-it-GGUF
+(tool_name) -hf ggml-org/gemma-4-E4B-it-GGUF
 ```
 
 ## Finding more models:

tools/mtmd/tests.sh

@@ -91,11 +91,13 @@ add_test_vision "ggml-org/LightOnOCR-1B-1025-GGUF:Q8_0"
 add_test_vision "ggml-org/DeepSeek-OCR-GGUF:Q8_0" -p "Free OCR." --chat-template deepseek-ocr
 add_test_vision "ggml-org/dots.ocr-GGUF:Q8_0" -p "OCR"
 add_test_vision "ggml-org/HunyuanOCR-GGUF:Q8_0" -p "OCR"
+add_test_vision "ggml-org/gemma-4-E2B-it-GGUF:Q8_0" --jinja
 
 add_test_audio  "ggml-org/ultravox-v0_5-llama-3_2-1b-GGUF:Q8_0"
 add_test_audio  "ggml-org/Qwen2.5-Omni-3B-GGUF:Q4_K_M"
 add_test_audio  "ggml-org/Voxtral-Mini-3B-2507-GGUF:Q4_K_M"
 add_test_audio  "ggml-org/LFM2-Audio-1.5B-GGUF:Q8_0"
+add_test_audio  "ggml-org/gemma-4-E2B-it-GGUF:Q8_0" --jinja
 
 # to test the big models, run: ./tests.sh big
 if [ "$RUN_BIG_TESTS" = true ]; then