TSM-06: convert Group A services to TypeScript

[Justin Hammond (Justintime50)]

Summary

Converts Group A service modules to TypeScript and applies minimal typed compatibility fixes needed for the current base-service conversion, with runtime behavior preserved.

Changes in this PR

• renames Group A service files to .ts:
  • src/services/address_service.ts
  • src/services/parcel_service.ts
  • src/services/customs_info_service.ts
  • src/services/customs_item_service.ts
  • src/services/shipment_service.ts
• adds minimal type-safe wrapper map annotations where property writes are dynamic
• updates conversion helper callsites to pass params consistently with current base service signatures
• introduces no new ts-nocheck

Testing

• npm run typescript
• npm run build
• npx eslint src/services/address_service.ts src/services/parcel_service.ts src/services/customs_info_service.ts src/services/customs_item_service.ts src/services/shipment_service.ts
• npx vitest run test/services/address.test.js test/services/parcel.test.js test/services/customs_info.test.js test/services/customs_item.test.js test/services/shipment.test.js test/services/module_exports_compat.test.js

Notes

• targeted service suites above are blocked locally without EASYPOST_TEST_API_KEY; module export compatibility test is included in the command set.

[Alex Matthews (ralexmatthews)]

Hmmm... this looks like its more of a "just adding types for the sake of adding types" and less like implementing typescript checking. Lots of unknowns, anys, and general type omissions. I see lots of places where we introduce more any's, and while we technically have "explicit parameter and return types", I don't think most of them are actually helpful. So many are just

(params: Record<string, unknown>): Promise<unknown>

I might not be getting the point of this, and they are typed in the ./types/ directory. I don't know if we want to implement those in the source directly instead, or treat those as the source of truth or what, but it feels divergent.