fix(reader): Save/Cancel in the note editor closes the whole popover

Cancel only collapsed the editor section, and edit-mode saves only set
noteOpen=false — the minimized popover (colors/pencil/copy/delete) stayed
up. Explicit Save and Cancel now call hideSelectionPopover; color tweaks
with the editor open still keep it open.

web/src/reader/reader.ts

@@ -1758,9 +1758,9 @@ document.addEventListener("alpine:init", () => {
             id: p.id,
           });
         }
-        // Color tweaks made while the note editor is open keep the
-        // editor open — only the explicit save/close paths collapse it.
-        if (!keepNoteOpen) p.noteOpen = false;
+        // Explicit saves (the Save button) close the whole popover; color
+        // tweaks made while the note editor is open keep everything open.
+        if (!keepNoteOpen) this.hideSelectionPopover();
       } catch (_e) {
         /* ignore highlight errors */
       }