feat(shifts): /shift→/shifts, clickable activity log (shared event-detail), booth-style full-height layout

Three changes to the shift hub, addressing the report:

1. Route rename /shift → /shifts (matches the plural "Turnet" label and the
   section). /shift and /setup/shifts both redirect to /shifts; the header link
   and the operator-landing fallback point at /shifts.

2. The activity-log rows are now CLICKABLE and open the same read-only
   event-detail modal the booth live feed uses (full signed payload + entry/exit
   snapshots + chain provenance) — previously they were static rows. Extracted
   EVENT_STYLE, the feed row, the detail modal, and their helpers out of
   BoothScreen into a shared apps/web/src/ui/event-detail.tsx imported by both the
   booth and the shift log, so the two render and behave identically and can't
   drift.

3. Reworked the /shifts layout to fill the viewport like /booth: a fixed
   title + filters, then a two-pane area (shift list | activity log) where each
   pane scrolls independently (min-h-0/flex-1 + overflow-y-auto) instead of the
   whole page growing. ShiftActivityLog is now a flex column with a fixed header
   and a scrollable list.

Verified at runtime (Playwright): /shift redirects to /shifts, an activity row
opens the detail modal, the layout fills height, and the booth still works (0
console errors after the extraction). build+lint 14/14.

Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V

apps/web/src/lib/i18n/sq.ts

@@ -669,7 +669,7 @@ export const sq = {
     preset_week: "Javën e fundit",
     preset_month: "Muajin e fundit",
     preset_all: "Të gjitha",
-    preset_custom: "E zgjedhur",
+    preset_custom: "Zgjidh periudhë",
     selectAShift: "Zgjidh një turn për të parë aktivitetin e tij.",
     noActivity: "Asnjë aktivitet në këtë turn.",
     current: "aktual",