deps: Update pigeon to 26.0.0, from 25.5.0

Changelog:
  https://pub.dev/packages/pigeon/changelog#2600

Couple of changes for @proxyapi APIs, which we do not use.

Author: rajveermalviya

android/app/src/main/kotlin/com/zulip/flutter/AndroidNotifications.g.kt

@@ -1,4 +1,4 @@
-// Autogenerated from Pigeon (v25.5.0), do not edit directly.
+// Autogenerated from Pigeon (v26.0.0), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 @file:Suppress("UNCHECKED_CAST", "ArrayInDataClass")
 

ios/Runner/Notifications.g.swift

@@ -1,4 +1,4 @@
-// Autogenerated from Pigeon (v25.5.0), do not edit directly.
+// Autogenerated from Pigeon (v26.0.0), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 
 import Foundation

lib/host/android_notifications.g.dart

@@ -1,4 +1,4 @@
-// Autogenerated from Pigeon (v25.5.0), do not edit directly.
+// Autogenerated from Pigeon (v26.0.0), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 // ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import, unnecessary_parenthesis, prefer_null_aware_operators, omit_local_variable_types, unused_shown_name, unnecessary_import, no_leading_underscores_for_local_identifiers
 

lib/host/notifications.g.dart

@@ -1,4 +1,4 @@
-// Autogenerated from Pigeon (v25.5.0), do not edit directly.
+// Autogenerated from Pigeon (v26.0.0), do not edit directly.
 // See also: https://pub.dev/packages/pigeon
 // ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import, unnecessary_parenthesis, prefer_null_aware_operators, omit_local_variable_types, unused_shown_name, unnecessary_import, no_leading_underscores_for_local_identifiers
 

pubspec.lock

@@ -834,10 +834,10 @@ packages:
     dependency: "direct dev"
     description:
       name: pigeon
-      sha256: "5889b1a88204ed646229447a898e8c3389a8f906b087ea1d3d4b09338730b3c9"
+      sha256: b65acb352dc5a5f8615d074a83419388cbcc249f07c6d8c78b5bc16680a55dda
       url: "https://pub.dev"
     source: hosted
-    version: "25.5.0"
+    version: "26.0.0"
   platform:
     dependency: transitive
     description:

pubspec.yaml

@@ -102,7 +102,7 @@ dev_dependencies:
   ini: ^2.1.0
   json_serializable: ^6.5.4
   legacy_checks: ^0.1.0
-  pigeon: ^25.3.1
+  pigeon: ^26.0.0
   stack_trace: ^1.11.1
   test: ^1.23.1
   test_api: ^0.7.3