Fix admin CSS not loading and quirks mode issues

Fixed multiple issues in admin panel:

1. CSS path: modern-normalize.css → modern-normalize.min.css
   (File is actually named .min.css)

2. Icon path: assets/icon.svg → /assets/admin_favicon.svg
   (Was relative, now absolute; correct filename)

3. Navigation: /admin/list.php → /admin/
   (list.php was renamed to index.php)

4. Short PHP tags: <? → <?php
   (Better compatibility, some servers don't enable short_open_tag)

5. Quirks mode warning was due to CSS not loading, not DOCTYPE
   (DOCTYPE was already present)

Files modified:
- public/admin/inc/head.php (main fixes)
- public/admin/index.php (short tags)
- public/admin/add.php (short tags)
- public/admin/import.php (short tags)

Need to redeploy for production: just deploy

public/assets/admin.css

@@ -0,0 +1,180 @@
+main {
+  margin: 1.2rem 0;
+}
+
+.filters {
+  background: #f5f5f5;
+  padding: 1rem;
+  margin-bottom: 2rem;
+  border-radius: 4px;
+}
+
+.filters form {
+  display: flex;
+  gap: 1rem;
+  flex-wrap: wrap;
+  align-items: end;
+}
+
+.filters fieldset {
+  margin: 0;
+  padding: 0;
+  border: none;
+  min-width: 200px;
+}
+
+.thesis-table {
+  width: 100%;
+  border-collapse: collapse;
+}
+
+.thesis-table th,
+.thesis-table td {
+  padding: 0.75rem;
+  text-align: left;
+  border-bottom: 1px solid #ddd;
+}
+
+.thesis-table th {
+  background: #f0f0f0;
+  font-weight: bold;
+}
+
+.thesis-table tr:hover {
+  background: #f9f9f9;
+}
+
+.thesis-title {
+  font-weight: bold;
+}
+
+.thesis-subtitle {
+  font-style: italic;
+  color: #666;
+  font-size: 0.9em;
+}
+
+.status-badge {
+  display: inline-block;
+  padding: 0.25rem 0.5rem;
+  border-radius: 3px;
+  font-size: 0.85em;
+}
+
+.status-pending {
+  background: #ffd700;
+  color: #000;
+}
+
+.status-published {
+  background: #90ee90;
+  color: #000;
+}
+
+.actions {
+  display: flex;
+  gap: 0.5rem;
+}
+
+.btn {
+  padding: 0.35rem 0.75rem;
+  border-radius: 3px;
+  text-decoration: none;
+  font-size: 0.9em;
+  display: inline-block;
+}
+
+.btn-view {
+  background: #4a90e2;
+  color: white;
+}
+
+.btn-edit {
+  background: #f39c12;
+  color: white;
+}
+
+.btn-publish {
+  background: #27ae60;
+  color: white;
+  border: none;
+  cursor: pointer;
+}
+
+.btn-unpublish {
+  background: #95a5a6;
+  color: white;
+  border: none;
+  cursor: pointer;
+}
+
+.publish-form {
+  display: inline;
+  margin: 0;
+}
+
+.stats {
+  display: flex;
+  gap: 2rem;
+  margin-bottom: 2rem;
+  flex-wrap: wrap;
+}
+
+.stat-card {
+  background: #f5f5f5;
+  padding: 1rem;
+  border-radius: 4px;
+  min-width: 150px;
+}
+
+.stat-number {
+  font-size: 2em;
+  font-weight: bold;
+  color: #4a90e2;
+}
+
+.stat-label {
+  color: #666;
+  font-size: 0.9em;
+}
+
+.bulk-actions {
+  background: #f5f5f5;
+  padding: 1rem;
+  margin-bottom: 1rem;
+  border-radius: 4px;
+  display: flex;
+  gap: 1rem;
+  align-items: center;
+}
+
+.bulk-actions-buttons {
+  display: flex;
+  gap: 0.5rem;
+}
+
+.btn-bulk-publish {
+  background: #27ae60;
+  color: white;
+  border: none;
+  cursor: pointer;
+  padding: 0.5rem 1rem;
+  border-radius: 3px;
+}
+
+.btn-bulk-unpublish {
+  background: #95a5a6;
+  color: white;
+  border: none;
+  cursor: pointer;
+  padding: 0.5rem 1rem;
+  border-radius: 3px;
+}
+
+.select-checkbox {
+  cursor: pointer;
+}
+
+.select-all-checkbox {
+  cursor: pointer;
+}