feat: add NovitaAI as LLM provider

Add NovitaAI as a first-class provider with dedicated model selection
flow, live pricing, and authoritative context length resolution.

- Register provider in PROVIDER_REGISTRY, HERMES_OVERLAYS, and all
  alias/label maps (ID: novita, aliases: novita-ai, novitaai)
- Add dedicated _model_flow_novita() with 3-tier model list fallback:
  Novita API → models.dev → static curated list
- Fetch live pricing from /v1/models with correct unit conversion
  (input_token_price_per_m is 0.0001 USD per Mtok)
- Add Novita-specific context length resolution (step 4b) in
  get_model_context_length(), prioritized over models.dev/OpenRouter
- Register api.novita.ai in _URL_TO_PROVIDER to prevent early return
  from the custom-endpoint code path
- Add models.dev mapping (novita → novita-ai)
- Add default auxiliary model (deepseek/deepseek-v3-0324)
- Add NOVITA_API_KEY to test isolation (conftest.py)
- Update docs: providers page, env vars reference, CLI reference,
  .env.example, README, and landing page

hermes_cli/models.py

@@ -445,6 +445,14 @@ _PROVIDER_MODELS: dict[str, list[str]] = {
     # Azure Foundry: user-provided endpoint and model.
     # Empty list because models depend on the endpoint configuration.
     "azure-foundry": [],
+    "novita": [
+        "moonshotai/kimi-k2.5",
+        "minimax/minimax-m2.7",
+        "zai-org/glm-5",
+        "deepseek/deepseek-v3-0324",
+        "deepseek/deepseek-r1-0528",
+        "qwen/qwen3-235b-a22b-fp8",
+    ],
 }
 
 # Vercel AI Gateway: derive the bare-model-id catalog from the curated
@@ -905,6 +913,7 @@ class ProviderEntry(NamedTuple):
 CANONICAL_PROVIDERS: list[ProviderEntry] = [
     ProviderEntry("nous",           "Nous Portal",              "Nous Portal (Nous Research subscription)"),
     ProviderEntry("openrouter",     "OpenRouter",               "OpenRouter (100+ models, pay-per-use)"),
+    ProviderEntry("novita",         "NovitaAI",                 "NovitaAI (90+ models, pay-per-use)"),
     ProviderEntry("lmstudio",       "LM Studio",                "LM Studio (local desktop app with built-in model server)"),
     ProviderEntry("anthropic",      "Anthropic",                "Anthropic (Claude models — API key or Claude Code)"),
     ProviderEntry("openai-codex",   "OpenAI Codex",             "OpenAI Codex"),
@@ -1014,6 +1023,8 @@ _PROVIDER_ALIASES = {
     "hf": "huggingface",
     "hugging-face": "huggingface",
     "huggingface-hub": "huggingface",
+    "novita-ai": "novita",
+    "novitaai": "novita",
     "mimo": "xiaomi",
     "xiaomi-mimo": "xiaomi",
     "tencent": "tencent-tokenhub",
@@ -1494,7 +1505,7 @@ def _resolve_nous_pricing_credentials() -> tuple[str, str]:
 
 
 def get_pricing_for_provider(provider: str, *, force_refresh: bool = False) -> dict[str, dict[str, str]]:
-    """Return live pricing for providers that support it (openrouter, nous, ai-gateway)."""
+    """Return live pricing for providers that support it (openrouter, nous, ai-gateway, novita)."""
     normalized = normalize_provider(provider)
     if normalized == "openrouter":
         return fetch_models_with_pricing(
@@ -1504,6 +1515,8 @@ def get_pricing_for_provider(provider: str, *, force_refresh: bool = False) -> d
         )
     if normalized == "ai-gateway":
         return fetch_ai_gateway_pricing(force_refresh=force_refresh)
+    if normalized == "novita":
+        return _fetch_novita_pricing()
     if normalized == "nous":
         api_key, base_url = _resolve_nous_pricing_credentials()
         if base_url:
@@ -1520,6 +1533,50 @@ def get_pricing_for_provider(provider: str, *, force_refresh: bool = False) -> d
     return {}
 
 
+def _fetch_novita_pricing(timeout: float = 8.0) -> dict[str, dict[str, str]]:
+    """Fetch pricing from NovitaAI /v1/models.
+
+    NovitaAI returns input/output prices per million tokens in units of
+    0.0001 USD. Convert them to the per-token strings used by the shared
+    pricing formatter.
+    """
+    api_key = os.getenv("NOVITA_API_KEY", "").strip()
+    if not api_key:
+        return {}
+
+    base_url = os.getenv("NOVITA_BASE_URL", "").strip() or "https://api.novita.ai/openai/v1"
+    url = base_url.rstrip("/") + "/models"
+    headers = {
+        "Authorization": f"Bearer {api_key}",
+        "Accept": "application/json",
+        "User-Agent": _HERMES_USER_AGENT,
+    }
+
+    try:
+        req = urllib.request.Request(url, headers=headers)
+        with urllib.request.urlopen(req, timeout=timeout) as resp:
+            payload = json.loads(resp.read().decode())
+    except Exception:
+        return {}
+
+    result: dict[str, dict[str, str]] = {}
+    for item in payload.get("data", []):
+        if not isinstance(item, dict):
+            continue
+        mid = item.get("id")
+        if not mid:
+            continue
+        inp = item.get("input_token_price_per_m")
+        out = item.get("output_token_price_per_m")
+        if inp is None and out is None:
+            continue
+        result[str(mid)] = {
+            "prompt": str(float(inp or 0) / 10_000 / 1_000_000),
+            "completion": str(float(out or 0) / 10_000 / 1_000_000),
+        }
+    return result
+
+
 # All provider IDs and aliases that are valid for the provider:model syntax.
 _KNOWN_PROVIDER_NAMES: set[str] = (
     set(_PROVIDER_LABELS.keys())