Refactor provider transport modules

crates/aether-provider-transport/src/vertex/mod.rs

@@ -0,0 +1,24 @@
+mod auth;
+mod context;
+mod policy;
+mod url;
+
+pub use auth::{
+    resolve_local_vertex_api_key_query_auth, VertexApiKeyQueryAuth, VERTEX_API_KEY_QUERY_PARAM,
+};
+pub use context::{
+    is_vertex_api_key_transport_context, looks_like_vertex_ai_host, uses_vertex_api_key_query_auth,
+};
+pub use policy::{
+    local_vertex_api_key_gemini_transport_unsupported_reason_with_network,
+    supports_local_vertex_api_key_gemini_transport,
+    supports_local_vertex_api_key_gemini_transport_with_network,
+    supports_local_vertex_api_key_imagen_transport,
+    supports_local_vertex_api_key_imagen_transport_with_network,
+};
+pub use url::{
+    build_vertex_api_key_gemini_content_url, build_vertex_api_key_imagen_content_url,
+    VERTEX_API_KEY_BASE_URL,
+};
+
+pub const PROVIDER_TYPE: &str = "vertex_ai";