perf: prevent import hanging with timeouts and batching

- verifyAndFixInteractionModesCount: paginated DB queries (500/batch)
  instead of loading all items into memory at once
- withFurniDataLock: add 60s chain timeout to prevent deadlocks
  when a lock holder stalls or crashes
- withGamedataLock: same timeout protection for gamedata locks
- conversion-pool: add 60s per-job timeout, fall back to main thread
- furni/batch: abort signal + post_import progress events + skip
  post-import steps when client disconnects
- furni/batch-regen: abort signal + early exit when disconnected
- clone/sync-all: pre-fetch furnidata once per source instead of
  per item (eliminates 2000+ redundant fetches)
- sse-client: add 60s idle timeout to prevent infinite hangs

src/lib/services/furni-import.ts

@@ -1128,83 +1128,84 @@ export async function verifyAndFixInteractionModesCount(): Promise<{
 	let fixed = 0;
 	let checked = 0;
 	let skipped = 0;
+	const BATCH_SIZE = 500;
 
 	try {
-		const allItems = await db
-			.select({
-				id: ItemsBase.id,
-				itemName: ItemsBase.itemName,
-				publicName: ItemsBase.publicName,
-				allowSit: ItemsBase.allowSit,
-				allowLay: ItemsBase.allowLay,
-				allowWalk: ItemsBase.allowWalk,
-				interactionType: ItemsBase.interactionType,
-				interactionModesCount: ItemsBase.interactionModesCount,
-			})
-			.from(ItemsBase);
+		let offset = 0;
+		while (true) {
+			const batch = await db
+				.select({
+					id: ItemsBase.id,
+					itemName: ItemsBase.itemName,
+					publicName: ItemsBase.publicName,
+					allowSit: ItemsBase.allowSit,
+					allowLay: ItemsBase.allowLay,
+					allowWalk: ItemsBase.allowWalk,
+					interactionType: ItemsBase.interactionType,
+					interactionModesCount: ItemsBase.interactionModesCount,
+				})
+				.from(ItemsBase)
+				.limit(BATCH_SIZE)
+				.offset(offset);
 
-		for (const item of allItems) {
-			checked++;
-			const realFlags = await lookupRealFurniFlags(item.itemName);
+			if (batch.length === 0) break;
+			offset += batch.length;
+			checked += batch.length;
 
-			// Real data absent → do not guess, leave the item untouched.
-			if (realFlags.source === "none") {
-				skipped++;
-				continue;
-			}
+			for (const item of batch) {
+				const realFlags = await lookupRealFurniFlags(item.itemName);
 
-			const animationModes = await realNitroModes(item.itemName);
-			const auto = autoDetectInteraction(item.itemName, item.publicName, {
-				cansiton: realFlags.cansiton,
-				canlayon: realFlags.canlayon,
-				canstandon: realFlags.canstandon,
-				// Furnidata flags are curated → authoritative over keywords.
-				hasActionData: true,
-				animationStates: animationModes,
-			});
+				if (realFlags.source === "none") {
+					skipped++;
+					continue;
+				}
 
-			const changes: Partial<Record<string, unknown>> = {};
-			// allow_sit/lay/walk of 2 is emulator-special (e.g. tents lay=2,
-			// walk-through walk=2) — never overwrite those with a 0/1.
-			if (
-				item.allowSit !== 2 &&
-				(item.allowSit ? 1 : 0) !== (auto.canSit ? 1 : 0)
-			)
-				changes.allowSit = auto.canSit ? 1 : 0;
-			if (
-				item.allowLay !== 2 &&
-				(item.allowLay ? 1 : 0) !== (auto.canLay ? 1 : 0)
-			)
-				changes.allowLay = auto.canLay ? 1 : 0;
-			if (
-				item.allowWalk !== 2 &&
-				(item.allowWalk ? 1 : 0) !== (auto.canStand ? 1 : 0)
-			)
-				changes.allowWalk = auto.canStand ? 1 : 0;
-			if ((item.interactionModesCount ?? 0) !== auto.interactionModesCount)
-				changes.interactionModesCount = auto.interactionModesCount;
-			// Only fill interaction_type when the DB still has the generic
-			// "default" (nothing emulator-specific configured). Never overwrite
-			// an existing handler type (e.g. intelligence_bookcase, nest, wf_*)
-			// — those are emulator semantics that real furnidata cannot replace.
-			if (
-				(item.interactionType === "default" || !item.interactionType) &&
-				auto.interactionType !== "default"
-			) {
-				changes.interactionType = auto.interactionType;
-			}
+				const animationModes = await realNitroModes(item.itemName);
+				const auto = autoDetectInteraction(item.itemName, item.publicName, {
+					cansiton: realFlags.cansiton,
+					canlayon: realFlags.canlayon,
+					canstandon: realFlags.canstandon,
+					hasActionData: true,
+					animationStates: animationModes,
+				});
 
-			if (Object.keys(changes).length > 0) {
-				try {
-					await db
-						.update(ItemsBase)
-						.set(changes)
-						.where(eq(ItemsBase.id, item.id));
-					fixed++;
-				} catch (err) {
-					errors.push(
-						`Failed to fix ${item.itemName}: ${(err as Error).message}`,
-					);
+				const changes: Partial<Record<string, unknown>> = {};
+				if (
+					item.allowSit !== 2 &&
+					(item.allowSit ? 1 : 0) !== (auto.canSit ? 1 : 0)
+				)
+					changes.allowSit = auto.canSit ? 1 : 0;
+				if (
+					item.allowLay !== 2 &&
+					(item.allowLay ? 1 : 0) !== (auto.canLay ? 1 : 0)
+				)
+					changes.allowLay = auto.canLay ? 1 : 0;
+				if (
+					item.allowWalk !== 2 &&
+					(item.allowWalk ? 1 : 0) !== (auto.canStand ? 1 : 0)
+				)
+					changes.allowWalk = auto.canStand ? 1 : 0;
+				if ((item.interactionModesCount ?? 0) !== auto.interactionModesCount)
+					changes.interactionModesCount = auto.interactionModesCount;
+				if (
+					(item.interactionType === "default" || !item.interactionType) &&
+					auto.interactionType !== "default"
+				) {
+					changes.interactionType = auto.interactionType;
+				}
+
+				if (Object.keys(changes).length > 0) {
+					try {
+						await db
+							.update(ItemsBase)
+							.set(changes)
+							.where(eq(ItemsBase.id, item.id));
+						fixed++;
+					} catch (err) {
+						errors.push(
+							`Failed to fix ${item.itemName}: ${(err as Error).message}`,
+						);
+					}
 				}
 			}
 		}