fix(channels): tag-filter row folds overflow into "+N", keeps "…" pinned

The channel manager's tag-filter row wrapped the trailing "…" catalog-actions
menu onto a second line once the chips + Clear outgrew the width. Rework it as
one non-wrapping row: the TAGS editor trigger (left), a single-line chip lane
that collapses overflow into a "+N" pill whose popover holds the rest (still
toggleable), then Clear and the "…" menu pinned right — so "…" always stays on
the first line.

New TagFilterChips reuses the shared measure core (useChipOverflowFit +
fitChipsWithPill), the same compression the feed's applied-filter row uses.

frontend/src/i18n/locales/en/channels.json

@@ -52,7 +52,9 @@
     "create": "Create tag",
     "createPlaceholder": "New tag…",
     "createFailed": "Could not create the tag.",
-    "noTag": "No tag"
+    "noTag": "No tag",
+    "moreCount_one": "{{count}} more tag",
+    "moreCount_other": "{{count}} more tags"
   },
   "loading": "Loading channels…",
   "empty": "No channels.",

frontend/src/i18n/locales/hu/channels.json

@@ -52,7 +52,9 @@
     "create": "Címke létrehozása",
     "createPlaceholder": "Új címke…",
     "createFailed": "A címke létrehozása nem sikerült.",
-    "noTag": "Nincs címke"
+    "noTag": "Nincs címke",
+    "moreCount_one": "még {{count}} címke",
+    "moreCount_other": "még {{count}} címke"
   },
   "loading": "Csatornák betöltése…",
   "empty": "Nincsenek csatornák.",