feat(proxy): enhance Traefik version notifications to show patch and minor upgrades

- Store both patch update and newer minor version information simultaneously
- Display patch update availability alongside minor version upgrades in notifications
- Add newer_branch_target and newer_branch_latest fields to traefik_outdated_info
- Update all notification channels (Discord, Telegram, Slack, Pushover, Email, Webhook)
- Show minor version in format (e.g., v3.6) for upgrade targets instead of patch version
- Enhance UI callouts with clearer messaging about available upgrades
- Remove verbose logging in favor of cleaner code structure
- Handle edge case where SSH command returns empty response

🤖 Generated with Claude Code

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

app/Models/Server.php

@@ -142,6 +142,7 @@ class Server extends BaseModel
 
     protected $casts = [
         'proxy' => SchemalessAttributes::class,
+        'traefik_outdated_info' => 'array',
         'logdrain_axiom_api_key' => 'encrypted',
         'logdrain_newrelic_license_key' => 'encrypted',
         'delete_unused_volumes' => 'boolean',
@@ -168,6 +169,7 @@ class Server extends BaseModel
         'hetzner_server_status',
         'is_validating',
         'detected_traefik_version',
+        'traefik_outdated_info',
     ];
 
     protected $guarded = [];