Add TimelineInstaller class for plugin management

Author: jedi58

src/Timeline/Installer/TimelineInstaller.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace Inachis\Timeline\Installer;
+
+use Inachis\Plugin\PluginInstallerInterface;
+
+final class TimelineInstaller implements PluginInstallerInterface
+{
+    public function install(): void
+    {
+        // seed default timeline data or setup permissions
+    }
+
+    public function update(string $from, string $to): void
+    {
+        // handle version upgrades
+    }
+
+    public function uninstall(): void
+    {
+        // clean up plugin-specific data
+    }
+}