feat(operations): fresh platform-operations implementation

Full rewrite of the installer (incl. the finish step), self-update pipeline,
settings store, cron webhook, dashboard/bootstrap surface, environment
manager, wizard login, config endpoint and shared helpers. Byte-compatible
public interfaces and observable behavior, including documented legacy
quirks; verified by the pilot behavioral suite and the full test suite.

app/Platform/Operations/Http/Requests/SettingRequest.php

@@ -0,0 +1,33 @@
+<?php
+
+namespace App\Platform\Operations\Http\Requests;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+/**
+ * Payload for a bulk write to the settings store.
+ */
+class SettingRequest extends FormRequest
+{
+    /**
+     * Access is decided by the `manage settings` ability in the controller,
+     * so the request itself lets everything through.
+     */
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    /**
+     * The map of options to write must be present; individual option names
+     * are free-form, so nothing below `settings` is constrained here.
+     *
+     * @return array<string, string>
+     */
+    public function rules(): array
+    {
+        return [
+            'settings' => 'required',
+        ];
+    }
+}