build: M1 Dockerized development stack with PHP skeleton, config/logging, Tailwind assets, and wrappers

Implements MeshVault M1 (issues #6–11):

- Four-service Docker Compose stack (nginx, PHP-FPM 8.3, PostgreSQL 17, Node assets)
- Slim 4 + PHP-DI routing with escaped PHP views and production/dev error handling
- Immutable validated AppConfig with redacted diagnostics
- JSON stdout Monolog logging with job-scoped context
- Tailwind CSS v4 deterministic locked builds with template scanning
- POSIX and PowerShell dev wrappers (up/down/test/lint/assets/watch)
- Startup config validation fails before FPM serves as unprivileged www-data
- migrate/seed explicitly unavailable until M2 (#12); #10 remains open

Verified via clean-start acceptance on remote host (keith@192.168.2.23).

config/container.php

@@ -0,0 +1,14 @@
+<?php
+
+declare(strict_types=1);
+
+use MeshVault\Config\AppConfig;
+use MeshVault\Http\View;
+use MeshVault\Logging\LoggerFactory;
+use Psr\Log\LoggerInterface;
+
+return static fn (AppConfig $config): array => [
+    AppConfig::class => $config,
+    View::class => new View(dirname(__DIR__) . '/templates'),
+    LoggerInterface::class => static fn (): LoggerInterface => LoggerFactory::create($config),
+];