fix(resume): use fab fab--primary pattern with text label

- fab fab--primary fab--label (same base as contact FAB)
- fab-primary__ico--pdf with cv.svg mask
- fab__label for text
- fab__spinner for loading state
- fab--label overrides fixed width from fab--primary

src/partials/fab-stack-resume.html

@@ -1,7 +1,7 @@
 <div class="fab-stack" aria-label="Быстрые действия">
-      <button type="button" class="btn btn--primary btn--flat btn--resume" data-resume-pdf-btn aria-label="Скачать резюме в PDF">
-        <span class="btn__icon" aria-hidden="true"></span>
-        <span>Скачать в PDF</span>
-        <span class="btn__spinner" aria-hidden="true"></span>
+      <button type="button" class="fab fab--primary fab--label" data-resume-pdf-btn aria-label="Скачать резюме в PDF">
+        <span class="fab-primary__ico fab-primary__ico--pdf" aria-hidden="true"></span>
+        <span class="fab__label">Скачать в PDF</span>
+        <span class="fab__spinner" aria-hidden="true"></span>
       </button>
     </div>