Fix copy functionality in Firefox (#32077)

## Summary

This pull request addresses an issue where the copy functionality was
not working in Firefox. The root cause was the absence of the
'clipboardWrite' permission in the manifest. To ensure consistency
across all supported browsers, the 'clipboardWrite' permission has been
added to the manifests for Chrome, Edge, and Firefox extensions.

Closes #31422 

## How did you test this change?

I ran the modified extension in all browsers (MacOS) and verified that
the copy functionality works in each.

https://github.com/user-attachments/assets/a41ff14b-3d65-409c-ac7f-1ccd72fa944a

Author: V3RON

packages/react-devtools-extensions/chrome/manifest.json

@@ -43,7 +43,8 @@
   "permissions": [
     "scripting",
     "storage",
-    "tabs"
+    "tabs",
+    "clipboardWrite"
   ],
   "host_permissions": [
     "<all_urls>"

packages/react-devtools-extensions/edge/manifest.json

@@ -43,7 +43,8 @@
   "permissions": [
     "scripting",
     "storage",
-    "tabs"
+    "tabs",
+    "clipboardWrite"
   ],
   "host_permissions": [
     "<all_urls>"

packages/react-devtools-extensions/firefox/manifest.json

@@ -50,7 +50,8 @@
   "permissions": [
     "scripting",
     "storage",
-    "tabs"
+    "tabs",
+    "clipboardWrite"
   ],
   "host_permissions": [
     "<all_urls>"