Fix comments UX regressions and HTMX/Turnstile behavior

- standardize comment and reply UI layout
- target replies with stable OOB container IDs
- remove stale empty-state on approved HTMX comments
- initialize Turnstile widgets after HTMX swaps
- add regression tests for empty-state, OOB targets, and reply form rerender

Refs #48

static/js/comments.js

@@ -0,0 +1,83 @@
+(function () {
+  function renderTurnstileWidgets(root) {
+    if (!root || !window.turnstile || typeof window.turnstile.render !== "function") {
+      return;
+    }
+
+    const widgets = [];
+    if (root.matches && root.matches(".cf-turnstile")) {
+      widgets.push(root);
+    }
+    if (root.querySelectorAll) {
+      widgets.push(...root.querySelectorAll(".cf-turnstile"));
+    }
+
+    widgets.forEach(function (widget) {
+      if (widget.dataset.turnstileRendered === "true") {
+        return;
+      }
+      if (widget.querySelector("iframe")) {
+        widget.dataset.turnstileRendered = "true";
+        return;
+      }
+
+      const sitekey = widget.dataset.sitekey;
+      if (!sitekey) {
+        return;
+      }
+
+      const options = {
+        sitekey: sitekey,
+        theme: widget.dataset.theme || "auto",
+      };
+      if (widget.dataset.size) {
+        options.size = widget.dataset.size;
+      }
+      if (widget.dataset.action) {
+        options.action = widget.dataset.action;
+      }
+      if (widget.dataset.appearance) {
+        options.appearance = widget.dataset.appearance;
+      }
+
+      window.turnstile.render(widget, options);
+      widget.dataset.turnstileRendered = "true";
+    });
+  }
+
+  function syncCommentsEmptyState() {
+    const emptyState = document.getElementById("comments-empty-state");
+    const commentsList = document.getElementById("comments-list");
+    if (!emptyState || !commentsList) {
+      return;
+    }
+
+    const hasComments = commentsList.querySelector("[data-comment-item='true']") !== null;
+    emptyState.classList.toggle("hidden", hasComments);
+  }
+
+  function onTurnstileReady(root) {
+    if (!window.turnstile || typeof window.turnstile.ready !== "function") {
+      return;
+    }
+    window.turnstile.ready(function () {
+      renderTurnstileWidgets(root || document);
+    });
+  }
+
+  document.addEventListener("DOMContentLoaded", function () {
+    syncCommentsEmptyState();
+    onTurnstileReady(document);
+  });
+
+  document.addEventListener("htmx:afterSwap", function (event) {
+    const target = event.detail && event.detail.target ? event.detail.target : document;
+    syncCommentsEmptyState();
+    onTurnstileReady(target);
+  });
+
+  window.addEventListener("load", function () {
+    syncCommentsEmptyState();
+    onTurnstileReady(document);
+  });
+})();