Add provider abstraction for Gemini, Claude, and OpenAI backends

routeforge/gateway.py

@@ -0,0 +1,15 @@
+"""Single-endpoint gateway that fans requests out to whichever backend
+provider is configured."""
+
+from .providers import PROVIDERS
+
+
+class Gateway:
+    def __init__(self, default_provider="gemini"):
+        self.default_provider = default_provider
+
+    def route(self, provider_name=None):
+        provider_name = provider_name or self.default_provider
+        if provider_name not in PROVIDERS:
+            raise ValueError(f"unknown provider: {provider_name}")
+        return PROVIDERS[provider_name]

routeforge/providers.py

@@ -0,0 +1,17 @@
+"""Provider adapters for RouteForge."""
+
+
+class Provider:
+    def __init__(self, name, base_url):
+        self.name = name
+        self.base_url = base_url
+
+    def complete(self, prompt):
+        raise NotImplementedError("wire up a real backend client here")
+
+
+PROVIDERS = {
+    "gemini": Provider("gemini", "https://generativelanguage.googleapis.com"),
+    "claude": Provider("claude", "https://api.anthropic.com"),
+    "openai": Provider("openai", "https://api.openai.com"),
+}