chores: tsconfig module: node20 and import extensions (#2974)

`module: node20` introduced in Typescript 5.9 as a stable replacement
for `nodenext`:

https://www.typescriptlang.org/docs/handbook/release-notes/typescript-5-9.html#support-for---module-node20

The recommended combination is with `moduleResolution: node16`:
microsoft/TypeScript#61805

That change implies relative imports to have extensions, however, it's
possible to change them directly to `.ts`, which will also reiterate and
resolve #2289 . It will enable running typescript natively by Node.js
without `tsx`. It may also come handy if I decide to publish to JSR.

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

- Chores
- Project build and compiler settings standardized; JSON imports made
explicit and some tooling switched to static JSON imports.
- Refactor
- Internal module references normalized to explicit TypeScript entries;
some runtime identifiers now derive from environment-provided build
metadata.
- Tests
- Test imports updated for explicit module resolution; migration tests
expanded with additional valid cases.
- Style
- New lint rules encourage .ts extensions for local imports and
discourage direct package.json imports.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: RobinTail

compat-test/quick-start.spec.ts

@@ -8,7 +8,7 @@ import {
   expect,
   test,
 } from "vitest";
-import { givePort } from "../tools/ports";
+import { givePort } from "../tools/ports.ts";
 
 describe("ESM Test", async () => {
   let out = "";

eslint.config.js

@@ -24,6 +24,10 @@ const importConcerns = [
     selector: "ImportDeclaration[source.value=/^zod/] > ImportDefaultSpecifier",
     message: "do import { z } instead",
   },
+  {
+    selector: "ImportDeclaration[source.value=/\\.js$/]",
+    message: "use .ts extension for relative imports",
+  },
   ...builtinModules.map((mod) => ({
     selector: `ImportDeclaration[source.value='${mod}']`,
     message: `use node:${mod} for the built-in module`,
@@ -64,6 +68,10 @@ const performanceConcerns = [
     selector: "MemberExpression[object.name='R'] > Identifier[name='union']", // #2599
     message: "R.union() is 1.5x slower than [...Set().add()]",
   },
+  {
+    selector: "ImportDeclaration[source.value=/package.json$/]", // #2974
+    message: "it can not be tree shaken, use tsdown and process.env instead",
+  },
 ];
 
 const tsFactoryConcerns = [

esm-test/quick-start.spec.ts

@@ -1,5 +1,5 @@
 import { spawn } from "node:child_process";
-import { givePort } from "../tools/ports";
+import { givePort } from "../tools/ports.ts";
 
 describe("ESM Test", async () => {
   let out = "";

esm-test/tsconfig.json

@@ -1,7 +1,7 @@
 import { BuiltinLogger, createConfig } from "express-zod-api";
 import ui from "swagger-ui-express";
 import createHttpError from "http-errors";
-import { givePort } from "../tools/ports";
+import { givePort } from "../tools/ports.ts";
 import qs from "qs";
 
 export const config = createConfig({

example/config.ts

@@ -1,7 +1,7 @@
 import createHttpError from "http-errors";
 import assert from "node:assert/strict";
 import { z } from "zod";
-import { statusDependingFactory } from "../factories";
+import { statusDependingFactory } from "../factories.ts";
 
 const namePart = z.string().regex(/^\w+$/);
 

example/endpoints/create-user.ts

@@ -1,7 +1,7 @@
 import createHttpError from "http-errors";
 import assert from "node:assert/strict";
 import { z } from "zod";
-import { noContentFactory } from "../factories";
+import { noContentFactory } from "../factories.ts";
 
 /** @desc The endpoint demonstrates no content response established by its factory */
 export const deleteUserEndpoint = noContentFactory.buildVoid({

example/endpoints/delete-user.ts

@@ -1,5 +1,5 @@
 import { z } from "zod";
-import { arrayRespondingFactory } from "../factories";
+import { arrayRespondingFactory } from "../factories.ts";
 
 const roleSchema = z.enum(["manager", "operator", "admin"]);
 

example/endpoints/list-users.ts

@@ -2,7 +2,7 @@ import createHttpError from "http-errors";
 import assert from "node:assert/strict";
 import { z } from "zod";
 import { defaultEndpointsFactory } from "express-zod-api";
-import { methodProviderMiddleware } from "../middlewares";
+import { methodProviderMiddleware } from "../middlewares.ts";
 
 // Demonstrating circular schemas using z.object()
 const feature = z.object({

example/endpoints/retrieve-user.ts

@@ -1,5 +1,5 @@
 import { z } from "zod";
-import { fileSendingEndpointsFactory } from "../factories";
+import { fileSendingEndpointsFactory } from "../factories.ts";
 import { readFile } from "node:fs/promises";
 
 export const sendAvatarEndpoint = fileSendingEndpointsFactory.build({