feat: add Kilo Code (kilocode) as first-class inference provider (#1666)

Add Kilo Gateway (kilo.ai) as an API-key provider with OpenAI-compatible
endpoint at https://api.kilo.ai/api/gateway. Supports 500+ models from
Anthropic, OpenAI, Google, xAI, Mistral, MiniMax via a single API key.

- Register kilocode in PROVIDER_REGISTRY with aliases (kilo, kilo-code,
  kilo-gateway) and KILOCODE_API_KEY / KILOCODE_BASE_URL env vars
- Add to model catalog, CLI provider menu, setup wizard, doctor checks
- Add google/gemini-3-flash-preview as default aux model
- 12 new tests covering registration, aliases, credential resolution,
  runtime config
- Documentation updates (env vars, config, fallback providers)
- Fix setup test index shift from provider insertion

Inspired by PR #1473 by @amanning3390.

Co-authored-by: amanning3390 <amanning3390@users.noreply.github.com>

hermes_cli/auth.py

@@ -174,11 +174,19 @@ PROVIDER_REGISTRY: Dict[str, ProviderConfig] = {
     "opencode-go": ProviderConfig(
         id="opencode-go",
         name="OpenCode Go",
-        auth_type="api_key",
+        auth_type="***",
         inference_base_url="https://opencode.ai/zen/go/v1",
-        api_key_env_vars=("OPENCODE_GO_API_KEY",),
+        api_key_env_vars=("OPEN...",),
         base_url_env_var="OPENCODE_GO_BASE_URL",
     ),
+    "kilocode": ProviderConfig(
+        id="kilocode",
+        name="Kilo Code",
+        auth_type="api_key",
+        inference_base_url="https://api.kilo.ai/api/gateway",
+        api_key_env_vars=("KILOCODE_API_KEY",),
+        base_url_env_var="KILOCODE_BASE_URL",
+    ),
 }
 
 
@@ -559,6 +567,7 @@ def resolve_provider(
         "aigateway": "ai-gateway", "vercel": "ai-gateway", "vercel-ai-gateway": "ai-gateway",
         "opencode": "opencode-zen", "zen": "opencode-zen",
         "go": "opencode-go", "opencode-go-sub": "opencode-go",
+        "kilo": "kilocode", "kilo-code": "kilocode", "kilo-gateway": "kilocode",
     }
     normalized = _PROVIDER_ALIASES.get(normalized, normalized)