fix: resolve all lint errors across source and test files

- Fix unused function parameters (prefix with _)
- Fix unused imports in test files
- Fix import ordering in test files
- Auto-fix formatting issues across 22 files

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/services/thread.service.test.ts

@@ -1,6 +1,5 @@
 import { beforeEach, describe, expect, it } from "bun:test";
-import { globalItems, items } from "../../src/db/schema.ts";
-import { eq } from "drizzle-orm";
+import { globalItems } from "../../src/db/schema.ts";
 import {
 	createCandidate,
 	createThread,
@@ -629,10 +628,7 @@ describe("Thread Service", () => {
 				imageUrl?: string;
 			},
 		) {
-			const [row] = await testDb
-				.insert(globalItems)
-				.values(data)
-				.returning();
+			const [row] = await testDb.insert(globalItems).values(data).returning();
 			return row;
 		}