fix: restore VerifyInterception exception and align error handling with upstream

Remove the erroneous early-return guard (if !PageLevelInterceptionEnabled return)
that was silently swallowing calls to ContinueAsync/RespondAsync/AbortAsync when
interception was not enabled. The correct behavior, matching upstream Puppeteer,
is for VerifyInterception() to throw "Request Interception is not enabled!" so that
ShouldThrowIfInterceptionIsNotEnabled passes on Firefox BiDi.

Also align ContinueInternalAsync and RespondInternalAsync error handling with
upstream's handleError: re-throw header-validation errors (Invalid header, Unsafe
header, Expected "header", invalid argument) and silently swallow all other
WebDriverBiDiException protocol errors (cancelled request, etc.).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: kblok

lib/PuppeteerSharp/Bidi/BidiHttpRequest.cs

@@ -124,11 +124,6 @@ public override InterceptResolutionState InterceptResolutionState
     /// <inheritdoc />
     public override async Task ContinueAsync(Payload payloadOverrides = null, int? priority = null)
     {
-        if (!PageLevelInterceptionEnabled)
-        {
-            return;
-        }
-
         VerifyInterception();
 
         if (!CanBeIntercepted())
@@ -172,11 +167,6 @@ public override async Task RespondAsync(ResponseData response, int? priority = n
             throw new ArgumentNullException(nameof(response));
         }
 
-        if (!PageLevelInterceptionEnabled)
-        {
-            return;
-        }
-
         VerifyInterception();
 
         if (!CanBeIntercepted())
@@ -214,11 +204,6 @@ public override async Task RespondAsync(ResponseData response, int? priority = n
     /// <inheritdoc />
     public override async Task AbortAsync(RequestAbortErrorCode errorCode = RequestAbortErrorCode.Failed, int? priority = null)
     {
-        if (!PageLevelInterceptionEnabled)
-        {
-            return;
-        }
-
         VerifyInterception();
 
         if (!CanBeIntercepted())
@@ -480,10 +465,18 @@ await _request.ContinueRequestAsync(
 
             // Only swallow specific protocol errors that are safe to ignore.
             // Match upstream's handleError behavior.
-            if (ex is WebDriverBiDi.WebDriverBiDiException bidiEx &&
-                (bidiEx.Message.Contains("Invalid request id") ||
-                 bidiEx.Message.Contains("no such request")))
+            if (ex is WebDriverBiDi.WebDriverBiDiException bidiEx)
             {
+                // Re-throw header validation errors — the user should see those.
+                // Swallow all other protocol errors (request already cancelled, etc.).
+                if (bidiEx.Message.Contains("Invalid header") ||
+                    bidiEx.Message.Contains("Unsafe header") ||
+                    bidiEx.Message.Contains("Expected \"header\"") ||
+                    bidiEx.Message.Contains("invalid argument"))
+                {
+                    throw;
+                }
+
                 return;
             }
 
@@ -503,7 +496,6 @@ private async Task AbortInternalAsync()
         {
             IsInterceptResolutionHandled = false;
 
-            // Only swallow specific protocol errors that are safe to ignore.
             if (ex is WebDriverBiDi.WebDriverBiDiException bidiEx &&
                 (bidiEx.Message.Contains("Invalid request id") ||
                  bidiEx.Message.Contains("no such request")))
@@ -587,11 +579,18 @@ await _request.ProvideResponseAsync(
         {
             IsInterceptResolutionHandled = false;
 
-            // Only swallow specific protocol errors that are safe to ignore.
-            if (ex is WebDriverBiDi.WebDriverBiDiException bidiEx &&
-                (bidiEx.Message.Contains("Invalid request id") ||
-                 bidiEx.Message.Contains("no such request")))
+            if (ex is WebDriverBiDi.WebDriverBiDiException bidiEx)
             {
+                // Re-throw header validation errors — the user should see those.
+                // Swallow all other protocol errors (request already cancelled, etc.).
+                if (bidiEx.Message.Contains("Invalid header") ||
+                    bidiEx.Message.Contains("Unsafe header") ||
+                    bidiEx.Message.Contains("Expected \"header\"") ||
+                    bidiEx.Message.Contains("invalid argument"))
+                {
+                    throw;
+                }
+
                 return;
             }