Add note about change in Gears router into changelog

Author: bbrtj

Changes

@@ -12,6 +12,12 @@ Revision history for Thunderhorse
 	- Thunderhorse dependencies no longer ensure pagi-server will be installed (via PAGI distribution split)
 		- pagi-server is now a part of a separate PAGI::Server module, which is not a direct dependency for Thunderhorse
 
+	[Fixes]
+	- Router behavior was improved (via Gears 0.104 change)
+		- previously, declaring bridges as empty routes was hard, and required an empty route ('' instead of '/')
+		- Gears::Router added pattern_separator, which is set to '/' by default, and affects how paths are joined
+		- this makes sure bridges will not cause repeated '/' in routes if they are declared as '/'
+
 0.105 - 2026-05-25
 	[Changes]
 	- Context's stash is now created lazily