Add floating FlowFuse Expert dock to use-case pages

src/_includes/components/expert-dock.njk

@@ -0,0 +1,81 @@
+{# ============================================================
+   FLOATING FLOWFUSE EXPERT DOCK (use case pages only)
+   A fixed, floating widget that hovers above the page content with a
+   margin from the left/right/bottom edges, rounded corners and a drop
+   shadow (it does not span edge to edge). It reuses the EXISTING AI
+   Expert experience: the bar contains the same entry point used on
+   /ai/ (the "Describe your workflow" textarea + #tell-me-how-btn), and
+   includes the shared ai-expert-modal component. No chat engine is
+   duplicated here.
+
+   The outer wrapper is transparent and click-through (pointer-events-none)
+   so the gutters either side of the floating card never block the page;
+   the inner card re-enables pointer events.
+   ============================================================ #}
+{% set dockSlug = page.fileSlug %}
+
+<div id="expert-dock"
+     role="region"
+     aria-label="Ask the FlowFuse Expert"
+     class="fixed inset-x-4 bottom-4 sm:bottom-6 z-40 pointer-events-none">
+    <div class="max-w-screen-xl mx-auto pointer-events-auto rounded-2xl border border-indigo-100 bg-white/95 backdrop-blur shadow-[0_12px_40px_-10px_rgba(49,46,129,0.45)] px-4 sm:px-6 py-3 flex items-center gap-3">
+        <div class="hidden sm:flex items-center gap-2 flex-shrink-0">
+            <div class="w-24 h-6">{% include "components/flowfuse-wordmark.njk" %}</div>
+            <span class="text-sm font-semibold text-gray-700">Expert</span>
+        </div>
+        <div class="textarea-wrapper relative flex-1 min-w-0">
+            <textarea
+                aria-label="Describe your workflow"
+                rows="1"
+                placeholder="Ask the FlowFuse Expert about {{ title }}..."
+                class="w-full resize-none bg-gray-50 border border-gray-300 rounded-full py-2.5 px-4 pr-4 text-sm text-gray-700 placeholder-gray-400 focus:outline-none focus:border-indigo-500 h-11 leading-6 overflow-hidden"></textarea>
+        </div>
+        <button id="tell-me-how-btn"
+                class="ff-btn ff-btn--highlight uppercase whitespace-nowrap px-5 py-2.5 flex-shrink-0"
+                onclick="if(typeof capture === 'function') capture('cta-expert-dock', {'usecase': '{{ dockSlug }}'})">
+            Ask
+        </button>
+        <button id="expert-dock-dismiss"
+                type="button"
+                aria-label="Dismiss the FlowFuse Expert"
+                class="flex-shrink-0 w-9 h-9 flex items-center justify-center rounded-full text-gray-400 hover:text-gray-600 hover:bg-gray-100 transition-colors">
+            <svg class="w-5 h-5" viewBox="0 0 24 24" fill="none" aria-hidden="true">
+                <path d="M18 6L6 18M6 6l12 12" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+            </svg>
+        </button>
+    </div>
+</div>
+
+{# Shared AI Expert modal (same entry point as /ai/). #}
+{% include "components/ai-expert-modal.njk" %}
+
+<script>
+(function () {
+    var dock = document.getElementById('expert-dock');
+    var dismiss = document.getElementById('expert-dock-dismiss');
+    if (!dock || !dismiss) return;
+
+    function hideDock() {
+        dock.style.display = 'none';
+        // Return focus to the body in a predictable place for keyboard users.
+        var main = document.getElementById('main-content');
+        if (main) {
+            main.setAttribute('tabindex', '-1');
+            main.focus();
+        }
+    }
+
+    dismiss.addEventListener('click', hideDock);
+
+    // ESC dismisses the dock only when the Expert modal is not open
+    // (the modal handles its own ESC/focus-trap behaviour).
+    document.addEventListener('keydown', function (e) {
+        if (e.key !== 'Escape') return;
+        var modal = document.getElementById('ai-expert-modal');
+        var modalOpen = modal && !modal.classList.contains('hidden');
+        if (!modalOpen && dock.style.display !== 'none') {
+            hideDock();
+        }
+    });
+})();
+</script>

src/_includes/layouts/use-case.njk

@@ -161,5 +161,12 @@ sitemapPriority: 0.7
     {% set relatedTag = "usecase:" + page.fileSlug %}
     {% include "components/related-resources.njk" %}
 
-    <!-- spacer so sticky dock never overlaps the final content -->
+    <!-- spacer so the floating expert dock never overlaps the final content -->
+    <div class="w-full h-28"></div>
+
 </div>
+
+<!-- ============================================================
+     FLOATING FLOWFUSE EXPERT DOCK (use case pages only)
+============================================================ -->
+{% include "components/expert-dock.njk" %}