chore(v5): archive V5 implementation and remove runtime integration

Move V5 source, migrations, UI, scripts, and tests into documentation, then remove V5 routes, models, jobs, configuration, dependencies, and application hooks.

docs/v5/archive/app/Http/Controllers/V5/Concerns/ResolvesCurrentTeam.php.txt

@@ -0,0 +1,22 @@
+<?php
+
+namespace App\Http\Controllers\V5\Concerns;
+
+use App\Models\Team;
+use Illuminate\Http\Request;
+
+trait ResolvesCurrentTeam
+{
+    /**
+     * Resolve the current team set by the EnsureCurrentTeam middleware, or
+     * abort with a 404 so resources outside the team stay invisible.
+     */
+    protected function currentTeamOrFail(Request $request): Team
+    {
+        $currentTeam = $request->attributes->get('v5.currentTeam');
+
+        abort_unless($currentTeam instanceof Team, 404);
+
+        return $currentTeam;
+    }
+}