feat(web): switch to path-based URL strategy

Remove hash from URLs (/#/login -> /login) using usePathUrlStrategy().
Uses conditional imports to only apply on web, keeping mobile/desktop
builds unaffected.

Required for OIDC callback to work - Authentik redirects to /callback
which Flutter now recognizes as a route.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pubspec.yaml

@@ -16,7 +16,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 1.0.7+1
+version: 1.0.8+1
 
 environment:
   sdk: ^3.10.4
@@ -30,6 +30,8 @@ environment:
 dependencies:
   flutter:
     sdk: flutter
+  flutter_web_plugins:
+    sdk: flutter
 
   # State Management
   flutter_riverpod: ^3.0.0