Add connection review page with optional message on connection requests

- New GET route and template for reviewing individual connection requests
- Optional personal message field when sending connection requests
- Message visible to recipient on review page and connection list
- Dashboard "Review" button links to per-connection review page
- QR scan flow shows message prompt before sending request
- Fix accepted connections query: include both sent and received
- Fix url_for('uploaded_file') -> url_for('static', 'uploads/')
- Fix request.json -> request.is_json to avoid 415 on form POST
- Remove card from DOM on approve/reject instead of page reload

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

templates/attendee/connection_requests.html

@@ -23,7 +23,7 @@
             <div class="request-card">
                 <div class="request-profile">
                     {% if req.profile_picture %}
-                    <img src="{{ url_for('uploaded_file', filename=req.profile_picture) }}" alt="{{ req.first_name }}" class="profile-photo">
+                    <img src="{{ url_for('static', filename='uploads/' + req.profile_picture) }}" alt="{{ req.first_name }}" class="profile-photo">
                     {% else %}
                     <div class="profile-photo-placeholder"><span class="first-name">{{ req.first_name[0] }}</span><span class="last-name">{{ req.last_name[0] }}</span></div>
                     {% endif %}
@@ -32,12 +32,16 @@
                     <h3><span class="first-name">{{ req.first_name }}</span> <span class="last-name">{{ req.last_name }}</span></h3>
                     <p class="request-email">{{ req.email }}</p>
                     <p class="request-org">{{ req.organisation if req.organisation else '' }}{% if req.role %} - {{ req.role }}{% endif %}</p>
+                    {% if req.message %}
+                        <p class="request-message">"{{ req.message[:150] }}{% if req.message|length > 150 %}...{% endif %}"</p>
+                    {% endif %}
                     {% if req.introduction %}
                         <p class="request-intro">"{{ req.introduction }}"</p>
                     {% endif %}
                     <p class="request-time">{{ 'requested'|t }} {{ req.created_at|localized_date if req.created_at else 'recently' }}</p>
                 </div>
                 <div class="request-actions">
+                    <a href="{{ url_for('respond_to_connection', connection_id=req.id) }}" class="btn btn-outline btn-sm">{{ 'review'|t }}</a>
                     <button class="btn btn-success btn-sm respond-btn" data-connection-id="{{ req.id }}" data-action="approve">{{ 'approve'|t }}</button>
                     <button class="btn btn-danger btn-sm respond-btn" data-connection-id="{{ req.id }}" data-action="reject">{{ 'reject'|t }}</button>
                 </div>
@@ -68,7 +72,11 @@ document.querySelectorAll('.respond-btn').forEach(btn => {
             const data = await response.json();
 
             if (data.success) {
-                location.reload();
+                this.closest('.request-card').remove();
+                // If no requests left, reload to show the empty state
+                if (!document.querySelector('.request-card')) {
+                    location.reload();
+                }
             } else {
                 showToast(data.error || 'Error processing request', 'error');
             }