fix: ERR_REQUIRE_ESM error under CommonJS module system

[hzrd149]

This PR removes the explicit .js file extension set in vite.config.ts. This was causing issues when using the package with node because node will treat any .js file in a package as an ES module if the "type": "module" is set

This was only an issue when importing the package from a CJS context. for example

const {createRxNostr} = require("rx-nostr")

Would throw

/tmp/tmp.sesywPGnIr/test.cjs:1
const {createRxNostr} = require('rx-nostr')
                        ^

Error [ERR_REQUIRE_ESM]: require() of ES Module /tmp/tmp.sesywPGnIr/node_modules/.pnpm/[email protected]/node_modules/rx-nostr/dist/index.cjs.js from /tmp/tmp.sesywPGnIr/test.cjs not supported.
index.cjs.js is treated as an ES module file as it is a .js file whose nearest parent package.json contains "type": "module" which declares all .js files in that package scope as ES modules.
Instead either rename index.cjs.js to end in .cjs, change the requiring code to use dynamic import() which is available in all CommonJS modules, or change "type": "module" to "type": "commonjs" in /tmp/tmp.sesywPGnIr/node_modules/.pnpm/[email protected]/node_modules/rx-nostr/package.json to treat all .js files as CommonJS (using .mjs for all ES modules instead).

    at Object.<anonymous> (/tmp/tmp.sesywPGnIr/test.cjs:1:25) {
  code: 'ERR_REQUIRE_ESM'
}

Node.js v20.18.1

To fix this I removed the fileName option in the vite.config.ts which makes vite use the default .cjs and .mjs file extensions.

So now its possible to import the package with import or require

import { createRxNostr } from "rx-nostr"

const rxNostr = createRxNostr({})
console.log(rxNostr)

const { createRxNostr } = require('rx-nostr')

const rxNostr = createRxNostr({})
console.log(rxNostr)

[penpenpng]

Thank you for your contribution! I have one change request (or question).

[penpenpng]

Thanks a lot!