fix(eslint): remove stale suppressions from merged attachments code

ESLint --fix removes no-op suppression comments for rules not enabled
in our config. These were introduced by the attachments PR (#176) merge
and are cleaned up by the new ESLint 10 flat config.

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

Author: scottschreckengaust

cdk/src/handlers/shared/attachment-screening.ts

@@ -238,7 +238,7 @@ const PDF_EXTRACT_TIMEOUT_MS = 15_000;
 
 async function extractPdfText(content: Buffer, filename: string): Promise<string> {
   // Dynamic import — pdf-parse is only used for PDF attachments.
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+
   let pdfParseFn: (data: Buffer, options?: { max?: number }) => Promise<{ text: string }>;
   try {
     // pdf-parse uses a default export; handle both CJS and ESM module shapes.

cdk/src/handlers/shared/validation.ts

@@ -266,7 +266,7 @@ export const MAX_TOTAL_ATTACHMENT_SIZE_BYTES = 50 * 1024 * 1024;
 /** Compile-time exhaustiveness check for AttachmentType. */
 const ATTACHMENT_TYPE_LIST = ['image', 'file', 'url'] as const satisfies readonly AttachmentType[];
 type _AssertAttachmentExhaustive = Exclude<AttachmentType, (typeof ATTACHMENT_TYPE_LIST)[number]> extends never ? true : never;
-const _attachmentExhaustiveCheck: _AssertAttachmentExhaustive = true; // eslint-disable-line @typescript-eslint/no-unused-vars
+const _attachmentExhaustiveCheck: _AssertAttachmentExhaustive = true;
 const VALID_ATTACHMENT_TYPES = new Set<string>(ATTACHMENT_TYPE_LIST);
 
 /** Allowed image MIME types (PNG and JPEG only — passed directly to Bedrock). */