perf: hoist update() inner functions out of the tick path

updateIfIdle and updateIfWaitingToRoll were declared inside update(),
allocating two closures on every 32ms tick. They are now module-level
functions receiving the state explicitly. Behaviour is unchanged, as
proven by the characterisation suite.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PVTnCfesGNGwPQJwJ9FwoD

apps/server/src/stores/runtimeState.ts

@@ -637,7 +637,7 @@ export function updateCore(state: RuntimeState): UpdateResult {
   // 2. are we waiting to roll?
   if (state.timer.playback === Playback.Roll && state.timer.secondaryTimer !== null) {
     const clockHasCrossedMidnight = hasCrossedMidnight(previousClock, now);
-    return updateIfWaitingToRoll(clockHasCrossedMidnight);
+    return updateIfWaitingToRoll(state, clockHasCrossedMidnight);
   }
 
   // 3. at this point we know that we are playing an event
@@ -674,13 +674,16 @@ export function updateCore(state: RuntimeState): UpdateResult {
   getExpectedTimesCore(state);
 
   return { hasTimerFinished: finishedNow, hasSecondaryTimerFinished: false };
+}
 
-  function updateIfIdle() {
+// module level so the hot path does not allocate a closure on every tick
+function updateIfIdle(): UpdateResult {
   // if nothing is running, nothing to do
   return { hasTimerFinished: false, hasSecondaryTimerFinished: false };
 }
 
-  function updateIfWaitingToRoll(hasCrossedMidnight: boolean) {
+// module level so the hot path does not allocate a closure on every tick
+function updateIfWaitingToRoll(state: RuntimeState, hasCrossedMidnight: boolean): UpdateResult {
   // eslint-disable-next-line no-unused-labels -- dev code path
   DEV: {
     if (state.eventNow === null || state._timer.secondaryTarget === null) {
@@ -704,7 +707,6 @@ export function updateCore(state: RuntimeState): UpdateResult {
     hasSecondaryTimerFinished: state.timer.secondaryTimer <= 0,
   };
 }
-}
 
 export function roll(
   rundown: Rundown,