feat(api): support custom BYO API header override on client fetches and backend config

app/api/beat-audio/route.ts

@@ -24,7 +24,7 @@ export async function POST(req: Request) {
   }
 
   try {
-    const config = loadEngineConfig();
+    const config = loadEngineConfig(req.headers);
     const result = await requestBeatAudio(config, body);
     return NextResponse.json(result);
   } catch (err) {

app/api/insert-beat/route.ts

@@ -22,7 +22,7 @@ export async function POST(req: Request) {
   }
 
   try {
-    const config = loadEngineConfig();
+    const config = loadEngineConfig(req.headers);
     const result = await requestInsertBeat(config, body);
     return NextResponse.json(result);
   } catch (err) {

app/api/parse-style-image/route.ts

@@ -51,7 +51,7 @@ export async function POST(req: Request) {
   }
 
   try {
-    const config = loadEngineConfig();
+    const config = loadEngineConfig(req.headers);
     const raw = await analyzeImageDataUrl(
       config.vision,
       body.imageDataUrl,

app/api/scene/route.ts

@@ -23,7 +23,7 @@ export async function POST(req: Request) {
   }
 
   try {
-    const config = loadEngineConfig();
+    const config = loadEngineConfig(req.headers);
     const result = await requestScene(config, body);
     return NextResponse.json(result);
   } catch (err) {

app/api/start/route.ts

@@ -41,7 +41,7 @@ export async function POST(req: Request) {
   }
 
   try {
-    const config = loadEngineConfig();
+    const config = loadEngineConfig(req.headers);
     const result = await startSession(config, body);
     return NextResponse.json(result);
   } catch (err) {

app/api/vision/route.ts

@@ -42,7 +42,7 @@ export async function POST(req: Request) {
   }
 
   try {
-    const config = loadEngineConfig();
+    const config = loadEngineConfig(req.headers);
     const result = await visionDecide(config, body);
     return NextResponse.json(result);
   } catch (err) {