feat: Implement floors, locations, and racks management

- Added list, edit, and save functionalities for floors, locations, and racks.
- Enhanced UI with search and filter options for better usability.
- Implemented SVG upload for floor plans in the floors module.
- Added validation for required fields in the save processes.
- Improved navigation in the header to reflect new modules.
- Styled forms and tables for a consistent look and feel across modules.

app/modules/locations/edit.php

@@ -0,0 +1,161 @@
+<?php
+/**
+ * app/modules/locations/edit.php
+ *
+ * Standort anlegen/bearbeiten
+ */
+
+// =========================
+// Kontext bestimmen
+// =========================
+$locationId = (int)($_GET['id'] ?? 0);
+$location = null;
+
+if ($locationId > 0) {
+    $location = $sql->single(
+        "SELECT * FROM locations WHERE id = ?",
+        "i",
+        [$locationId]
+    );
+}
+
+$isEdit = !empty($location);
+$pageTitle = $isEdit ? "Standort bearbeiten: " . htmlspecialchars($location['name']) : "Neuer Standort";
+
+?>
+
+<div class="location-edit">
+    <h1><?php echo $pageTitle; ?></h1>
+
+    <form method="post" action="?module=locations&action=save" class="edit-form">
+
+        <?php if ($isEdit): ?>
+        <input type="hidden" name="id" value="<?php echo $locationId; ?>">
+        <?php endif; ?>
+
+        <!-- =========================
+             Basisdaten
+             ========================= -->
+        <fieldset>
+            <legend>Allgemein</legend>
+
+            <div class="form-group">
+                <label for="name">Name <span class="required">*</span></label>
+                <input type="text" id="name" name="name" required
+                    value="<?php echo htmlspecialchars($location['name'] ?? ''); ?>"
+                    placeholder="z.B. Hauptgebäude, Campus A, Außenstelle Berlin">
+            </div>
+
+            <div class="form-group">
+                <label for="comment">Beschreibung</label>
+                <textarea id="comment" name="comment" rows="3"
+                    placeholder="Adresse, Kontaktinformationen, Besonderheiten"><?php echo htmlspecialchars($location['comment'] ?? ''); ?></textarea>
+            </div>
+        </fieldset>
+
+        <!-- =========================
+             Aktionen
+             ========================= -->
+        <fieldset class="form-actions">
+            <button type="submit" class="button button-primary">Speichern</button>
+            <a href="?module=locations&action=list" class="button">Abbrechen</a>
+            <?php if ($isEdit): ?>
+                <a href="#" class="button button-danger" onclick="confirmDelete(<?php echo $locationId; ?>)">Löschen</a>
+            <?php endif; ?>
+        </fieldset>
+
+    </form>
+</div>
+
+<style>
+.location-edit {
+    max-width: 800px;
+    margin: 20px auto;
+    padding: 20px;
+}
+
+.edit-form {
+    background: white;
+    padding: 20px;
+    border: 1px solid #ddd;
+    border-radius: 8px;
+}
+
+.edit-form fieldset {
+    margin: 20px 0;
+    padding: 15px;
+    border: 1px solid #e0e0e0;
+    border-radius: 4px;
+}
+
+.edit-form legend {
+    padding: 0 10px;
+    font-weight: bold;
+    font-size: 1.1em;
+}
+
+.form-group {
+    margin: 15px 0;
+}
+
+.form-group label {
+    display: block;
+    margin-bottom: 5px;
+    font-weight: bold;
+}
+
+.form-group input[type="text"],
+.form-group textarea {
+    width: 100%;
+    padding: 8px 12px;
+    border: 1px solid #ddd;
+    border-radius: 4px;
+    font-family: inherit;
+}
+
+.form-group textarea {
+    resize: vertical;
+}
+
+.required {
+    color: red;
+}
+
+.form-actions {
+    display: flex;
+    gap: 10px;
+    margin-top: 30px;
+}
+
+.button {
+    padding: 10px 15px;
+    background: #007bff;
+    color: white;
+    text-decoration: none;
+    border-radius: 4px;
+    border: none;
+    cursor: pointer;
+    font-size: 0.95em;
+}
+
+.button-primary {
+    background: #28a745;
+}
+
+.button-danger {
+    background: #dc3545;
+}
+
+.button:hover {
+    opacity: 0.8;
+}
+</style>
+
+<script>
+function confirmDelete(id) {
+    if (confirm('Diesen Standort wirklich löschen? Alle Gebäude werden gelöscht.')) {
+        // TODO: AJAX-Delete implementieren
+        alert('Löschen noch nicht implementiert');
+    }
+}
+</script>