fix(api): 自定义渠道 - 移除浏览器 CORS 依赖

web/src/services/api/custom-channel-relay.ts

@@ -0,0 +1,28 @@
+import { isSystemProxyBaseUrl, resolveBackendApiUrl, type AiConfig } from "@/stores/use-config-store";
+
+type RelayConfig = Pick<AiConfig, "baseUrl" | "apiKey" | "apiFormat">;
+
+export type ChannelRequest = {
+    url: string;
+    headers: Record<string, string>;
+    credentials: RequestCredentials;
+};
+
+/** 自定义渠道统一经登录态后端中转，避免依赖第三方服务的浏览器 CORS。 */
+export function channelRequest(config: RelayConfig, upstreamUrl: string, headers: HeadersInit = {}): ChannelRequest {
+    const normalizedHeaders = new Headers(headers);
+    if (isSystemProxyBaseUrl(config.baseUrl)) {
+        return { url: upstreamUrl, headers: Object.fromEntries(normalizedHeaders.entries()), credentials: "include" };
+    }
+
+    const normalizedUpstreamUrl = new URL(upstreamUrl).toString();
+    normalizedHeaders.delete("x-goog-api-key");
+    normalizedHeaders.set("Authorization", `Bearer ${config.apiKey}`);
+    normalizedHeaders.set("X-Canvas-Upstream-URL", normalizedUpstreamUrl);
+    normalizedHeaders.set("X-Canvas-Upstream-Format", config.apiFormat === "gemini" ? "gemini" : "openai");
+    return {
+        url: resolveBackendApiUrl("/api/ai/custom"),
+        headers: Object.fromEntries(normalizedHeaders.entries()),
+        credentials: "include",
+    };
+}