feat(design): a video's one action list (C1) — the card's "…", the menu holds the rest (E28 S3e1)

- useContextMenu gains buttonProps (a row's visible "…" opens the same menu under the button; a
  second press closes it) and anchor (the element the menu came from, for a panel a row opens).
- ui/MoreButton; ActionMenu rows can run inGesture (a clipboard write inside the click, Safari).
- useVideoActions: one builder for a video's menu (play / restart, channel, watched, save, add to
  playlist, download, details, copy title / link, hide, reset, pin), composed by the feed and by
  Home's rails; the playlists and details panels open anchored beside the card (VideoFollowUp).
- The card keeps watched / save / add to playlist and the "…": on the picture on hover (the
  duration steps aside), in the rows' action column; on touch only a 44px "…" beside the title.
  Download, hide, reset and the hover info card leave the card.
- The title is selectable: a click ending a selection neither plays nor follows the link.
- DESIGN.md: how C1 is built + the log row.

docs/DESIGN.md

@@ -270,6 +270,14 @@ Which actions are visible and which live in a menu.
     A playlist item's X column goes: Delete key plus an undo toast.
   - Downloads, Notifications and the Scheduler get a menu (they have none today); a page's destructive
     header action ("Clear everything", "Purge discovery") goes into the header's "…".
+- **Built as:** one `useContextMenu` per list; the row spreads `triggerProps` (right-click, long-press,
+  Shift+F10) and its "…" is `ui/MoreButton` with `buttonProps` (the same menu, under the button; a second
+  press closes it). An object's list is one builder (`useVideoActions` for a video, composed by the feed
+  and by Home's rails); a row that opens a panel ("Add to playlist…", "Details") anchors it to
+  `menu.anchor`, the element the menu came from. "Copy title" / "Copy link" come from `useCopyItems` and
+  run inside the click (`inGesture`, Safari's clipboard rule). The card's hover row sits on its picture
+  (the duration steps aside while it shows); on touch the toggles are gone and a 44px "…" sits beside
+  the title (`.touch-only`).
 - **Background menu:** a right-click on EMPTY content area (not over text, inputs, links or media) may open
   a page menu. It only mirrors page-scope actions that already exist in the toolbar (sort, view, quick
   filters, select all); it adds no new function. Shift+right-click falls through to the browser's own menu.
@@ -403,5 +411,6 @@ Wherever there is text, the user can select it and copy it, and no click action
 | 2026-09-26 | Page band built (B4)        | Controls only in the band (intros scroll); the fold shows the same row in place; one `h1` per page (`PageHeading` steps the hidden one aside); `SectionLabel` headings; Skip to content | A popover of the folded filters; the page title kept visible                                          | A folded row is still the same controls, nothing duplicated; the rail and the tab title already name the page                                                        |
 | 2026-09-26 | Fade built (B9)             | `fade-below` on sticky toolbars and table headers; the scroller mask where the band sits on the backdrop                                                                                | A painted band over the backdrop                                                                      | The backdrop is the colour under the band, so fading the content into it is the same edge                                                                            |
 | 2026-09-26 | Viewport units              | `dvh` everywhere (the Plex player stage with S3f)                                                                                                                                       | `vh` / `h-screen`                                                                                     | `100vh` hides the last rows under a tablet browser's toolbar                                                                                                         |
+| 2026-09-26 | Video actions built (C1)    | One list per video (menu, right-click, long-press, "…"); the card keeps watched / save / add to playlist on its picture on hover; download, details, copy, hide, reset in the menu      | The six-button row under the card and the hover ⓘ                                                     | The menu is the one door every device has; the card loses a line of height and the touch card its row of 28px buttons                                                |
 | 2026-09-24 | Chip family                 | One `Chip` (filter / token / tag / suggest / ghost) + `DismissibleChip`; nothing under 24; the lint rule "no raw `<button>` outside ui/"                                                | Five chip geometries in five files                                                                    | The applied-filter row, the tag cells, the year picker and the saved-view editor each drew their own chip; a one-letter tag was 21px wide                            |
 | 2026-09-24 | Button families             | `Button` / `IconButton` / `Pressable` / chips / `DragHandle`; `lg` 40 for a hero CTA; pills and a 48 Play on media (from C5)                                                            | Every button hand-painted                                                                             | 268 hand-rolled buttons in 79 files drifted into as many looks; the ladder only holds if every button stands on it                                                   |