feat(FEAT-3): reslot on inline init change + gate field

Reslot: handleInlineInitiative now sorts participants[] by init desc
(stable, tie-break original index) via sortParticipantsByInitiative.
Display + AdminView reflect new order after init edit. Not a blind
re-sort — only moved element changes position.

Gate: inline init field disabled when combat active + not paused.
Matches drag gating. DM must pause to edit initiative mid-combat.

Tests: InitiativeReslot.test.js (2). RED first (no reslot, Goblin stayed
at idx 1), green after impl (reslots to idx 0). Field gate test.

src/App.js

@@ -949,7 +949,10 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
     }
   };
 
-  // Inline initiative edit (FEAT-3): blur/Enter commits. Re-syncs turnOrderIds.
+  // Inline initiative edit (FEAT-3): blur/Enter commits. Reslots participant
+  // into correct list position (stable sort by init desc, tie-break original
+  // index). Display + AdminView both reflect new order. Pre-combat only —
+  // field gated to !started||paused elsewhere.
   const handleInlineInitiative = async (participantId, value) => {
     if (!db) return;
     const n = parseInt(value, 10);
@@ -957,10 +960,11 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
     const updatedParticipants = participants.map(p =>
       p.id === participantId ? { ...p, initiative: n } : p
     );
+    const reslotted = sortParticipantsByInitiative(updatedParticipants, participants);
     try {
       await storage.updateDoc(encounterPath, {
-        participants: updatedParticipants,
-        ...(encounter.isStarted ? syncTurnOrder(updatedParticipants) : {}),
+        participants: reslotted,
+        ...syncTurnOrder(reslotted),
       });
     } catch (err) {
       console.error("Error updating initiative:", err);
@@ -1483,11 +1487,12 @@ function ParticipantManager({ encounter, encounterPath, campaignCharacters }) {
                           key={p.initiative}
                           min="0"
                           max="99"
+                          disabled={encounter.isStarted && !encounter.isPaused}
                           onChange={(e) => { if (e.target.value.length > 2) e.target.value = e.target.value.slice(0, 2); }}
                           onFocus={(e) => e.target.select()}
                           onBlur={(e) => { if (e.target.value !== String(p.initiative)) handleInlineInitiative(p.id, e.target.value); }}
                           onKeyDown={(e) => { if (e.key === 'Enter') e.target.blur(); }}
-                          className="w-10 px-1 py-0.5 bg-stone-800 border border-stone-700 rounded-md shadow-sm text-white text-sm focus:outline-none focus:ring-1 focus:ring-amber-600 focus:border-amber-600"
+                          className="w-10 px-1 py-0.5 bg-stone-800 border border-stone-700 rounded-md shadow-sm text-white text-sm focus:outline-none focus:ring-1 focus:ring-amber-600 focus:border-amber-600 disabled:opacity-50 disabled:cursor-not-allowed"
                           aria-label={`Initiative for ${p.name}`}
                         />
                       </span>