fix: use explicit env var mapping for Together AI provider in vault middleware

The vault middleware built env var names using f'{provider.upper()}_API_KEY'
which produces TOGETHER_AI_API_KEY for the 'together_ai' provider kind.
The actual env var is TOGETHERAI_API_KEY (no underscore), matching the
frontend (llmProviders.ts, transforms.ts), backend (env.py), and the
Daytona sandbox runner (daytona.py).

Add an explicit _PROVIDER_ENV_VAR_MAP dict (mirroring the Daytona runner
pattern) that maps each provider kind to its correct env var name, with
fallback to the original f-string pattern for any future providers.

Closes #3659

Author: GanJiaKouN16

sdks/python/agenta/sdk/middlewares/running/vault.py

@@ -37,6 +37,28 @@
 if "mistral" not in _PROVIDER_KINDS:
     _PROVIDER_KINDS.append("mistral")
 
+# Mapping from provider kind to environment variable name.
+# Most providers follow the pattern PROVIDER_API_KEY, but some have
+# underscores in their kind string (e.g. "together_ai") where the env
+# var drops the underscore (TOGETHERAI_API_KEY). This explicit mapping
+# mirrors the one in the Daytona runner and the frontend llmProviders.ts.
+_PROVIDER_ENV_VAR_MAP: Dict[str, str] = {
+    "openai": "OPENAI_API_KEY",
+    "cohere": "COHERE_API_KEY",
+    "anyscale": "ANYSCALE_API_KEY",
+    "deepinfra": "DEEPINFRA_API_KEY",
+    "alephalpha": "ALEPHALPHA_API_KEY",
+    "groq": "GROQ_API_KEY",
+    "minimax": "MINIMAX_API_KEY",
+    "mistral": "MISTRAL_API_KEY",
+    "mistralai": "MISTRAL_API_KEY",
+    "anthropic": "ANTHROPIC_API_KEY",
+    "perplexityai": "PERPLEXITYAI_API_KEY",
+    "together_ai": "TOGETHERAI_API_KEY",
+    "openrouter": "OPENROUTER_API_KEY",
+    "gemini": "GEMINI_API_KEY",
+}
+
 _AUTH_ENABLED = (
     getenv("AGENTA_SERVICES_MIDDLEWARE_AUTH_ENABLED")
     or getenv("AGENTA_SERVICE_MIDDLEWARE_AUTH_ENABLED")
@@ -306,7 +328,7 @@ async def get_secrets(
     try:
         for provider_kind in _PROVIDER_KINDS:
             provider = provider_kind
-            key_name = f"{provider.upper()}_API_KEY"
+            key_name = _PROVIDER_ENV_VAR_MAP.get(provider, f"{provider.upper()}_API_KEY")
             key = getenv(key_name)
 
             if not key: