[AiAssistance] Add http/2 pseudo headers to allow list

According to Gemini:
These headers are header fields that begin with a colon (:)
and are used to convey essential information about a request or response,
such as the method, path, authority, and scheme.

They effectively replace the HTTP/1.1 request line and status line.

Fixed: 399100945
Change-Id: I9850a0a77e92ce7696d6741de990f6004c635965
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6300644
Commit-Queue: Alex Rudenko <[email protected]>
Auto-Submit: Ergün Erdoğmuş <[email protected]>
Reviewed-by: Alex Rudenko <[email protected]>

Author: ergunsh

front_end/panels/ai_assistance/data_formatters/NetworkRequestFormatter.ts

@@ -167,6 +167,10 @@ Request initiator chain:\n${this.formatRequestInitiatorChain()}`;
 
 // Header names that could be included in the prompt, lowercase.
 const allowedHeaders = new Set([
+  ':authority',
+  ':method',
+  ':path',
+  ':scheme',
   'a-im',
   'accept-ch',
   'accept-charset',