Add NVIDIA logo and update company mappings

- Added logo-nvidia.svg asset for NVIDIA branding
- Added NVIDIA and Nemotron to COMPANY_LOGO_MAP
- Added NVIDIA and Nemotron to MODEL_COUNTRY_MAP (US company)

Co-authored-by: openhands <openhands@all-hands.dev>

leaderboard_transformer.py

@@ -38,6 +38,8 @@ COMPANY_LOGO_MAP = {
     "kimi": {"path": "assets/logo-moonshot.svg", "name": "Moonshot"},
     "moonshot": {"path": "assets/logo-moonshot.svg", "name": "Moonshot"},
     "minimax": {"path": "assets/logo-minimax.svg", "name": "MiniMax"},
+    "nvidia": {"path": "assets/logo-nvidia.svg", "name": "NVIDIA"},
+    "nemotron": {"path": "assets/logo-nvidia.svg", "name": "NVIDIA"},
 }
 
 # Openness icon mapping
@@ -62,6 +64,7 @@ MODEL_COUNTRY_MAP = {
     "meta": "us", "llama": "us",
     "xai": "us", "grok": "us",
     "cohere": "us", "command": "us",
+    "nvidia": "us", "nemotron": "us",
     # China companies
     "deepseek": "cn",
     "qwen": "cn", "alibaba": "cn",