feat(astrolabe): add Nextcloud PHP app for MCP server management

Adds a native Nextcloud app "Astroglobe" that provides:
- Personal settings: OAuth authorization for background MCP access
- Admin settings: Server status and vector sync monitoring
- API endpoints for MCP server communication

The app uses PKCE OAuth flow to obtain tokens for the MCP server,
enabling features like background vector sync per ADR-018.

Includes:
- PHP app structure (controllers, services, settings)
- Vue.js frontend components
- Docker compose mount configuration
- Installation hook for development testing
- ADR-018 documentation

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

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

third_party/astroglobe/.php-cs-fixer.dist.php

@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+require_once './vendor-bin/cs-fixer/vendor/autoload.php';
+
+use Nextcloud\CodingStandard\Config;
+
+$config = new Config();
+$config
+	->getFinder()
+	->notPath('build')
+	->notPath('l10n')
+	->notPath('node_modules')
+	->notPath('src')
+	->notPath('vendor')
+	->in(__DIR__);
+
+return $config;