P21: player seats + two-way live play + offline handoff

Players claim a seat (GM approves) and drive their own character live —
HP/slots/resources/conditions/dice broadcast to the table — via new seat
protocol messages and per-seat ownership enforced in RoomHub. GM persists
player edits (charactersRepo.update → liveQuery → rebroadcast). Offline dev:
"Share with player" encodes a claim link (src/lib/sync/playerLink.ts) → /player
imports the character locally for full-sheet editing, bundled back as an
offlineSnapshot on seat claim for GM review.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/features/characters/CharacterSheet.tsx

@@ -3,7 +3,8 @@ import { Link } from '@tanstack/react-router';
 import type { Character } from '@/lib/schemas';
 import type { AbilityKey, CharacterRulesInput, ProficiencyRank, SystemId } from '@/lib/rules';
 import { getSystem, ABILITY_ABBR } from '@/lib/rules';
-import { charactersRepo } from '@/lib/db/repositories';
+import { charactersRepo, campaignsRepo } from '@/lib/db/repositories';
+import { encodeClaim } from '@/lib/sync/playerLink';
 import { PF2E_SAVES } from '@/lib/rules/pf2e/skills';
 import { useDebouncedCallback } from '@/lib/useDebouncedCallback';
 import { rollCheck } from '@/lib/useRoll';
@@ -37,6 +38,15 @@ export function CharacterSheet({ character }: { character: Character }) {
   const [c, setC] = useState<Character>(character);
   const [levelUp, setLevelUp] = useState(false);
   const [genScores, setGenScores] = useState(false);
+  const [shared, setShared] = useState(false);
+
+  const shareWithPlayer = async () => {
+    const campaign = await campaignsRepo.get(c.campaignId);
+    const link = `${location.origin}/player?c=${encodeClaim({ character: c, campaignName: campaign?.name ?? 'Campaign', campaignSystem: c.system })}`;
+    try { await navigator.clipboard?.writeText(link); } catch { /* clipboard blocked */ }
+    setShared(true);
+    setTimeout(() => setShared(false), 1500);
+  };
   const save = useDebouncedCallback((next: Character) => {
     // Persist everything except identity/timestamps (update() stamps updatedAt).
     const { id, campaignId: _campaignId, createdAt: _createdAt, updatedAt: _updatedAt, ...rest } = next;
@@ -90,6 +100,7 @@ export function CharacterSheet({ character }: { character: Character }) {
         </span>
         <div className="ml-auto flex items-center gap-2">
           <span className="text-sm text-muted">{profLabel}</span>
+          {c.kind === 'pc' && <Button size="sm" variant="ghost" onClick={() => void shareWithPlayer()} title="Copy a link the player opens to manage this character">{shared ? 'Link copied ✓' : 'Share with player'}</Button>}
           <Button size="sm" variant="secondary" onClick={() => setLevelUp(true)}>Level up</Button>
           <Button size="sm" variant="ghost" onClick={() => window.print()} title="Print / save as PDF">Print</Button>
         </div>