Chores: weekly goals with custom reward tiers (everyone or chosen people)

- Admin-set reward tiers; points count Monday to Sunday and restart each week
- Per-person weekly totals, chores done, progress bar toward the next reward, week history
- Mark given / undo when a reward is handed over
- Rewards can be for everyone or only chosen people
- "This week" card on the family board
- Tests and README updated

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

public/style.css

@@ -1060,3 +1060,6 @@ body.vizopen { overflow: hidden; }
 
 #devchip { position: fixed; top: calc(env(safe-area-inset-top, 0px) + 8px); right: 10px; z-index: 60; display: flex; align-items: center; gap: 8px; background: var(--panel); border: 1px solid var(--line); border-radius: 22px; padding: 4px 4px 4px 14px; box-shadow: 0 4px 14px rgba(0,0,0,.3); }
 #devchip .btn { min-height: 34px; padding: 0 14px; border-radius: 18px; } .devwho { display: flex; align-items: center; gap: 6px; } .devkid { font-style: normal; background: #2f9e6e; color: #fff; border-radius: 8px; padding: 1px 7px; font-size: 11px; font-weight: 700; }
+
+.crtick { position: absolute; top: 0; width: 2px; height: 100%; background: var(--text); opacity: .55; } .crearn { display: flex; align-items: center; gap: 10px; margin: 6px 0 0 52px; padding: 8px 10px; border-radius: 12px; background: var(--panel2); } .crearn .btn { min-height: 34px; padding: 0 12px; }
+.crdet { margin: 6px 0 0 52px; } .crdet summary { cursor: pointer; color: var(--muted); font-size: 14px; } .crwk { padding: 8px 0; border-bottom: 1px solid var(--line); } .crwk:last-child { border-bottom: 0; }