[TS7] fix(types): type media provider request payloads (#9141)

Validated in local merge-train (devbox-vm-06-dev002) @ combined-tip (FAST gates: typecheck/complexity/cognitive/changelog/vitest — only pre-existing audit.test.ts flake). Evidence: /home/diegosouzapw/dev/proxys/OmniRoute/.claude/worktrees/merge-train-20260805-222248-suite.log

open-sse/handlers/imageGeneration.ts

@@ -719,7 +719,7 @@ async function handleKieImageGeneration({
     baseUrl = `${providerConfig.baseUrl.replace(/\/$/, "")}/api/v1/jobs/createTask`;
     const input: Record<string, unknown> = {
       prompt,
-      aspect_ratio: mapImageSize(size, "1:1"),
+      aspect_ratio: mapImageSize(size),
     };
     if (imageUrl) {
       input.image_url = imageUrl;
@@ -737,7 +737,7 @@ async function handleKieImageGeneration({
 
     payload = {
       prompt,
-      size: mapImageSize(size, "1:1"),
+      size: mapImageSize(size),
       nVariants: body.n || 1,
     };
   }

open-sse/handlers/videoGeneration.ts

@@ -655,11 +655,11 @@ async function handleRunwayVideoGeneration({
   );
   const headers = buildRunwayHeaders(token);
 
-  const upstreamBody = {
+  // prettier-ignore
+  const upstreamBody: { model: typeof model; promptText: typeof body.prompt; ratio: typeof ratio; duration: typeof duration; promptImage?: typeof promptImage; seed?: number } = {
     model,
     promptText: body.prompt,
-    ratio,
-    duration,
+    ratio, duration,
   };
 
   if (useImageToVideo) upstreamBody.promptImage = promptImage;