[PM-31406] fix: TypeScript 5.9 type compatibility fixes for vault-owned code (#19191)

* fix: TypeScript 5.9 type compatibility fixes for vault-owned code

Add explicit `as BufferSource` casts and `Uint8Array` wrapping to satisfy
stricter type checking in TypeScript 5.9. Non-functional changes.

* Fix cli build

apps/cli/src/vault/create.command.ts

@@ -170,7 +170,7 @@ export class CreateCommand {
       const updatedCipher = await this.cipherService.saveAttachmentRawWithServer(
         cipher,
         fileName,
-        new Uint8Array(fileBuf).buffer,
+        new Uint8Array(fileBuf),
         activeUserId,
       );
       const decCipher = await this.cipherService.decrypt(updatedCipher, activeUserId);

libs/common/src/vault/abstractions/cipher.service.ts

@@ -169,7 +169,7 @@ export abstract class CipherService implements UserKeyRotationDataProvider<Ciphe
   abstract saveAttachmentRawWithServer(
     cipher: Cipher,
     filename: string,
-    data: ArrayBuffer,
+    data: Uint8Array,
     userId: UserId,
     admin?: boolean,
   ): Promise<Cipher>;

libs/common/src/vault/services/cipher.service.ts

@@ -1959,7 +1959,7 @@ export class CipherService implements CipherServiceAbstraction {
 
     const fd = new FormData();
     try {
-      const blob = new Blob([encData.buffer], { type: "application/octet-stream" });
+      const blob = new Blob([encData.buffer as BlobPart], { type: "application/octet-stream" });
       fd.append("key", dataEncKey[1].encryptedString);
       fd.append("data", blob, encFileName.encryptedString);
       fd.append("lastKnownRevisionDate", lastKnownRevisionDate.toISOString());

libs/vault/src/components/download-attachment/download-attachment.component.ts

@@ -120,7 +120,7 @@ export class DownloadAttachmentComponent {
 
       this.fileDownloadService.download({
         fileName: attachment.fileName,
-        blobData: decBuf,
+        blobData: decBuf as BlobPart,
       });
     } catch {
       this.toastService.showToast({