Address review: playable PLAY/NEXT, visible rename editor, accurate copy

- PLAY and NEXT continue into the following scenes, so they stay
  enabled while any scene in the project has a shot, not only the
  selected one.
- Renaming a shot drops the number and ellipsis so the editor is no
  longer hidden; qa-scene-controls checks a long rename stays visible.
- PLAY, NEXT, EDIT DETAILS and SHARE SCENE tooltips describe what the
  buttons do, translated in every shipped language.
- The primary actions and the file row keep a hover state.
- Docs: the EXPORT rename in DIRECTOR-SHARING and the playback button
  states in CURRENT-STATE are accurate.
- Test the voice "authoring" alias through set_panel_open.

src/ui/styles/scenes.css

@@ -223,6 +223,14 @@ html:not([lang='en']) #scene-panel .scene-controls .scene-btn {
   background: transparent;
 }
 
+/* Keep the shared hover on the restyled actions. */
+#scene-panel .scene-btn-primary:hover:not(:disabled),
+#scene-panel .scene-file-controls .scene-btn:hover:not(:disabled) {
+  color: var(--accent);
+  border-color: var(--accent);
+  background: color-mix(in srgb, var(--accent) 16%, transparent);
+}
+
 .scene-shot-hint {
   margin: 0 0 8px;
   font-size: 11px;
@@ -311,6 +319,16 @@ html:not([lang='en']) #scene-panel .scene-controls .scene-btn {
   color: var(--text-primary);
 }
 
+/* While renaming, the label holds only the editor at full width. */
+.scene-shot-label:has(.scene-shot-rename) {
+  overflow: visible;
+  white-space: normal;
+}
+
+.scene-shot-label:has(.scene-shot-rename)::before {
+  content: none;
+}
+
 /* Shots are numbered 01, 02… in playback order. */
 .scene-shot-label::before {
   content: counter(scene-shot, decimal-leading-zero);