fix: resolve pre-existing lint warnings

- Remove unused siteSettings import in auth-precheck.test.ts
- Replace non-null assertions with proper null checks in furni-data-i18n.ts
- Replace non-null assertions with proper null checks in conversion-pool.ts

src/lib/services/furni-data-i18n.ts

@@ -457,13 +457,17 @@ export async function buildLocalizedFurniDataFiles(
 					translatedWall = res.translatedWall;
 					total = res.total;
 				} else {
-					const r = localPrepared.get(preparedKey!)!;
+					const r = localPrepared.get(preparedKey ?? "");
+					if (!r)
+						throw new Error(
+							`Missing localPrepared entry for key ${String(preparedKey)}`,
+						);
 					const res = finalizeLangFile(r.cloned, r.pendingRefs, translations);
 					json = res.json;
 					translatedRoom = res.translatedRoom;
 					translatedWall = res.translatedWall;
 					total = res.total;
-					localPrepared.delete(preparedKey!);
+					if (preparedKey != null) localPrepared.delete(preparedKey);
 				}
 
 				const targets = await getLocalizedWritePaths(lang);
@@ -593,13 +597,17 @@ export async function patchLocalizedFurniDataEntries(
 					added = res.added;
 					total = res.total;
 				} else {
-					const r = localPrepared.get(localKey!)!;
+					const r = localPrepared.get(localKey ?? "");
+					if (!r)
+						throw new Error(
+							`Missing localPrepared entry for key ${String(localKey)}`,
+						);
 					const res = finalizePatch(r, translations);
 					json = res.json;
 					patched = res.patched;
 					added = res.added;
 					total = res.total;
-					localPrepared.delete(localKey!);
+					if (localKey != null) localPrepared.delete(localKey);
 				}
 
 				for (const target of targets) {

src/lib/services/swf/conversion-pool.ts

@@ -79,8 +79,9 @@ function ensurePool(): boolean {
 
 function pump() {
 	while (idle.length > 0 && queue.length > 0) {
-		const w = idle.pop()!;
-		const job = queue.shift()!;
+		const w = idle.pop();
+		const job = queue.shift();
+		if (!w || !job) break;
 		pending.set(job.req.id, { worker: w, job });
 		w.postMessage(job.req);
 	}