feat(providers): add Arcee AI as direct API provider

Adds Arcee AI as a standard direct provider (ARCEEAI_API_KEY) with
Trinity models: trinity-large-thinking, trinity-large-preview, trinity-mini.

Standard OpenAI-compatible provider checklist: auth.py, config.py,
models.py, main.py, providers.py, doctor.py, model_normalize.py,
model_metadata.py, setup.py, trajectory_compressor.py.

Based on PR #9274 by arthurbr11, simplified to a standard direct
provider without dual-endpoint OpenRouter routing.

hermes_cli/config.py

@@ -824,6 +824,22 @@ OPTIONAL_ENV_VARS = {
         "category": "provider",
         "advanced": True,
     },
+    "ARCEEAI_API_KEY": {
+        "description": "Arcee AI API key",
+        "prompt": "Arcee AI API key",
+        "url": "https://chat.arcee.ai/",
+        "password": True,
+        "category": "provider",
+        "advanced": True,
+    },
+    "ARCEE_BASE_URL": {
+        "description": "Arcee AI base URL override",
+        "prompt": "Arcee base URL (leave empty for default)",
+        "url": None,
+        "password": False,
+        "category": "provider",
+        "advanced": True,
+    },
     "MINIMAX_API_KEY": {
         "description": "MiniMax API key (international)",
         "prompt": "MiniMax API key",