chore(psr4): phase 1 — rename 7 top-level dirs to PascalCase

Atomic case-rename of the seven class-holding source directories to match the
PSR-4 namespace casing, plus every consequent path reference. No code logic
changes — pure structural rename. (config/content/resources/signals/migrations/
ministra/storage/tmp/vendor/www/bin stay lowercase.)

- git mv: core→Core, domain→Domain, infrastructure→Infrastructure,
  streaming→Streaming, modules→Modules, cli→Cli, public→Public (module subdirs
  like Modules/plex stay lowercase; loaded by ModuleLoader, not Composer).
- PHP filesystem paths updated across src/ + tests/: require/include, glob/scandir
  bases, view includes, asset/nginx-alias paths, autoload.php registerDirectories(),
  ModuleLoader/ModuleManager module roots, console.php discovery dirs.
- src/composer.json PSR-4 vendored-lib paths → Core/Parsing/...; vendor/ regenerated.
- nginx.conf: docroot + SCRIPT_FILENAME → Public/. SCRIPT_NAME and the public-facing
  /streaming/*.php compat routes are URLs, left unchanged.
- Build/CI: Makefile LB_DIRS / LB_DIRS_TO_REMOVE / LB_FILES_TO_REMOVE PascalCased
  (closes the LB-archive privileged-leak blocker); phpstan.dist.neon paths/
  scanDirectories/excludePaths; phpunit.xml.dist coverage; phpstan-baseline.neon
  regenerated (294→294 errors, no new resolution failures).
- migrations/deleted_files.txt: old lowercase trees listed for client cleanup
  (assumes case-sensitive FS — the supported Linux target).

Verified: grep-gate 0 live lowercase-dir require/include in src+tests; php -l clean;
PHPUnit 292/292; PHPStan no errors; Composer first / XC_Autoloader last in SPL stack;
global classes resolve from the renamed dirs.

tests/Unit/InterfaceContractTest.php

@@ -247,8 +247,8 @@ final class InterfaceContractTest extends TestCase {
     public function testMinistraModuleImplementsBoundaryInterface(): void {
         if (!class_exists(\XcVm\Module\Ministra\MinistraModule::class)) {
             $file = defined('MAIN_HOME')
-                ? MAIN_HOME . 'modules/ministra/MinistraModule.php'
-                : __DIR__ . '/../../src/modules/ministra/MinistraModule.php';
+                ? MAIN_HOME . 'Modules/ministra/MinistraModule.php'
+                : __DIR__ . '/../../src/Modules/ministra/MinistraModule.php';
             require_once $file;
         }
         $rc = new ReflectionClass(\XcVm\Module\Ministra\MinistraModule::class);