fix(channels): the Length column shows the sum alone

The "+N without length" line did not fit the 4.5 rem column (88 px of
text in a 56 px cell) and spilled into Tags. The owner wants no such
line there: the cell shows the summed hours, and the channel list no
longer sends a count nothing reads. A playlist's total keeps it.

docs/DESIGN.md

@@ -877,3 +877,4 @@ of a full-width panel and nothing on the right.
 | 2026-11-07 | Text over the picture sits on a dark panel (owner a)                    | The player's loading, stall and error text, the subtitle notice and the track OSD sit on one dark panel (`OVER_VIDEO`, black 75 %, a white 15 % edge)                                                                                                                                                                                                                                               | A shadow behind the letters; bare text as before                                                                                                                                                       | Bare white or red text was unreadable over a bright frame (seen live); the panel is the style the notices already had                                                                                                        |
 | 2026-11-07 | The panel over the picture is darker, its error the media red (owner a) | `OVER_VIDEO` is black 85 % under `media-scope`: an error on it is the media red in both themes                                                                                                                                                                                                                                                                                                      | Only the red changed (3.75:1 on a white frame); black 90 %                                                                                                                                             | A light theme's red was 1.6:1 on the 75 % panel over a white frame; now 5.47:1 at worst, white text too                                                                                                                      |
 | 2026-11-07 | A total's left-out videos are "without length" (owner b)                | A summed length names what it left out as "+N without length" / "+N hossz nélkül"                                                                                                                                                                                                                                                                                                                   | "+N live" as before; "+N stream"                                                                                                                                                                       | The count holds archives and upcoming streams too, which a card calls a stream or upcoming: "live" there named only one of them (One name per feature)                                                                       |
+| 2026-11-08 | The Channels table's Length is the sum alone (owner)                    | The table's Length cell shows the summed hours only; the "+N without length" stays on a playlist's total                                                                                                                                                                                                                                                                                            | The line wrapped in the column; the column widened to 6.5 rem                                                                                                                                          | The 4.5 rem column is sized for the sum: the longer line spilled into Tags (88 px in 56), and the owner wants no such line there                                                                                             |