Move plugins to manifest, pin Docker version, add Makefile

- Add plugins.txt listing all plugins for reproducible installs
- Add Makefile with setup/start/stop/install-plugins targets
- Remove user/plugins/ from git tracking
- Pin Docker image to 1.7.49.5-ls244

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

plugins/form/templates/forms/layouts/xhr.html.twig

@@ -1,25 +0,0 @@
-{% if form.xhr_submit == true %}
-  {# Ensure xhr-submitter.js is loaded BEFORE the inline JS that uses it #}
-  {% do assets.addJs('plugin://form/assets/xhr-submitter.js', {'group': 'bottom', 'priority': 101, 'position': 'before'}) %}
-  {% do assets.addInlineJs("
-    document.addEventListener('DOMContentLoaded', () => {
-        // This now primarily sets up the *potential* for XHR submission
-        // It might not attach the listener directly if recaptcha is present
-        attachFormSubmitListener('" ~ form.id ~ "');
-
-        // Re-run captcha initializers *if* the form was loaded via XHR initially
-        // This covers edge cases, might not be strictly needed if captcha script handles DOMContentLoaded
-        const formElement = document.getElementById('" ~ form.id ~ "');
-        if (formElement && window.GravRecaptchaInitializers) {
-            const initializerFuncName = 'initRecaptcha_" ~ form.id ~ "';
-            if (typeof window.GravRecaptchaInitializers[initializerFuncName] === 'function') {
-                 // Check if it needs init (e.g., if container exists but no widget/listener)
-                 // For simplicity, just call it again; the init function should be idempotent
-                 // window.GravRecaptchaInitializers[initializerFuncName]();
-            }
-        }
-    });",
-    {'group': 'bottom', 'priority': 100, 'position': 'before'}) %}
-    {% do assets.addJs('plugin://form/assets/captcha/recaptcha-handler.js', {'group': 'bottom', 'priority': 99, 'position': 'before'}) %}
-    {% do assets.addJs('plugin://form/assets/captcha/turnstile-handler.js', {'group': 'bottom', 'priority': 98, 'position': 'before'}) %}
-{% endif %}