Convert project to ESM + type module

[techsmyth]

Description

As a developer I want to be able to use the latest packages.

Part of Phase 3 of Epic alkem-io/alkemio#1536. Should be deferred until NestJS 12 ships native ESM support (~Q3 2026).

Acceptance criteria

• Wait for NestJS 12 stable release with native ESM support
• Migrate tsconfig module from commonjs to ESM output
• Add "type": "module" to package.json
• Update moduleResolution to node16 or nodenext
• Use full relative file paths for imports (e.g., ./index.js)
• Use the node: protocol for Node.js built-in imports
• Replace graphql-upload@13 with ESM-compatible alternative (graphql-upload-ts or graphql-upload@17)
• Wrap TypeORM entity relations with Relation type to avoid circular dependency issues
• Audit and update all ESM-only / CJS-only dependencies
• Update build scripts and Dockerfile CMD if needed
• All existing tests pass

Additional Context

NestJS 12 (~Q3 2026) will make ESM the default module system. Key challenges:

• graphql-upload v14+ is ESM-only — current v13 is CJS
• TypeORM circular dependencies need Relation wrapper in ESM
• Some packages (chalk, node-fetch, ora, execa) have gone ESM-only in recent versions
• Node 24's require(esm) helps bridge the gap during transition

References:

• https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c#how-can-i-make-my-typescript-project-output-esm
• NestJS v12 PR

Dependencies

• NestJS 12 stable release
• Phase 1 (Apollo 5 + NestJS 11) and Phase 2 (Node 24) should be completed first