feat(portal): add app metadata and variables management

app/static/styles.css

@@ -443,13 +443,77 @@ button:hover,
 }
 
 input,
-select {
+select,
+textarea {
     padding: 8px;
     border: 1px solid var(--border);
     border-radius: 8px;
     background: white;
 }
 
+textarea {
+    min-height: 92px;
+    resize: vertical;
+}
+
+.metadata-form {
+    display: grid;
+    grid-template-columns: minmax(160px, 240px) minmax(280px, 1fr);
+    gap: 12px 16px;
+    align-items: center;
+    max-width: 980px;
+}
+
+.metadata-form label {
+    color: var(--secondary);
+    font-weight: 800;
+}
+
+.metadata-form input,
+.metadata-form select,
+.metadata-form textarea {
+    width: 100%;
+}
+
+.checkbox-label {
+    display: inline-flex;
+    align-items: center;
+    gap: 8px;
+}
+
+.checkbox-label input {
+    width: auto;
+}
+
+.form-actions {
+    grid-column: 2;
+}
+
+.detail-tabs {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 8px;
+    margin: 0 0 18px;
+}
+
+.add-variable-form {
+    margin-top: 18px;
+}
+
+.add-variable-form h3 {
+    grid-column: 1 / -1;
+    margin: 0;
+    color: var(--secondary);
+}
+
+.variable-form {
+    display: grid;
+    grid-template-columns: minmax(140px, 1fr) minmax(160px, 1fr) auto auto;
+    gap: 8px;
+    align-items: center;
+    margin-bottom: 8px;
+}
+
 input[readonly] {
     width: 100%;
     font-family: monospace;
@@ -844,18 +908,26 @@ pre {
     }
 
     .filter-form,
-    .inline-form {
+    .inline-form,
+    .metadata-form,
+    .variable-form {
         align-items: stretch;
+        display: flex;
         flex-direction: column;
     }
 
     input,
     select,
+    textarea,
     button,
     .btn {
         width: 100%;
     }
 
+    .form-actions {
+        grid-column: auto;
+    }
+
     .btn + .btn {
         margin-left: 0;
         margin-top: 8px;