chore: add environment configuration for Stagehand

- Set the environment to "BROWSERBASE" in the Stagehand initialization.
- Enhanced debugging by adding console logs for element evaluation in the file input check.

Author: udaysvc

examples/upload_test.ts

@@ -18,6 +18,7 @@ async function main() {
 
   const stagehand = new Stagehand({
     ...StagehandConfig,
+    env: "BROWSERBASE",
     verbose: 1,
     modelName: "openai/gpt-4o-mini",
   });

lib/index.ts

@@ -978,11 +978,17 @@ export class Stagehand {
         // If this is a file input → set directly
         const isFileInput = await locator
           .evaluate(
-            (el): boolean =>
-              el.tagName.toLowerCase() === "input" &&
-              (el as HTMLInputElement).type === "file",
+            (el): boolean => {
+              const tagName = el.tagName.toLowerCase();
+              const type = (el as HTMLInputElement).type;
+              console.log(`DEBUG: Element tagName=${tagName}, type=${type}`);
+              return tagName === "input" && type === "file";
+            },
           )
-          .catch(() => false);
+          .catch((e) => {
+            console.log(`DEBUG: evaluate failed:`, e);
+            return false;
+          });
 
         if (isFileInput) {
           await locator.setInputFiles(filesArg);