feat(dees-simple-appdash): add nested sidebar subviews and preserve submit labels from slotted text

ts_web/elements/00group-form/dees-form-submit/dees-form-submit.ts

@@ -75,12 +75,23 @@ export class DeesFormSubmit extends DeesElement {
         .text=${this.text}
         ?disabled=${this.disabled}
         @clicked=${this.submit}
-      >
-        <slot></slot>
-      </dees-button>
+      ></dees-button>
     `;
   }
 
+  public async firstUpdated() {
+    // Capture light DOM text content as the button label. dees-button wipes
+    // its own light DOM during extractLightDom(), so we cannot simply forward
+    // a <slot> into it — we have to hoist the text onto the .text property
+    // ourselves before handing it to dees-button.
+    if (!this.text) {
+      const slotText = this.textContent?.trim();
+      if (slotText) {
+        this.text = slotText;
+      }
+    }
+  }
+
   public async submit() {
     if (this.disabled) {
       return;