fix: drop .js extensions on ep_etherpad-lite/* requires

0.6.6 added explicit .js extensions to ep_etherpad-lite/static/js/Changeset
and friends, planning to support strict ESM resolution. That broke
backward-compat with the current CJS etherpad: Node's CJS resolver
treats 'foo.js' as a literal filename, and the actual source on disk
is foo.ts (loaded via tsx). 'foo' without extension lets Node's
default extension list + tsx's .ts substitution both work.

Verified locally: 104/104 tests pass. CJS etherpad CI was failing
on 'Cannot find module ep_etherpad-lite/static/js/Changeset.js' from
ep_plugin_helpers/attributes-server.js.

Author: SamTV12345

attributes-server.js

@@ -9,7 +9,7 @@ const createLineAttributeExport = (config) => {
   const stylesForExport = () => exportStyles || '';
 
   const getLineHTMLForExport = async (hookName, context) => {
-    const Changeset = require('ep_etherpad-lite/static/js/Changeset.js');
+    const Changeset = require('ep_etherpad-lite/static/js/Changeset');
     let header = null;
     if (context.attribLine) {
       const opIter = Changeset.opIterator(context.attribLine);

message-relay.js

@@ -10,7 +10,7 @@ const createMessageRelay = (config) => {
     const message = data;
     if (action && message.action !== action) return;
 
-    const padMessageHandler = require('ep_etherpad-lite/node/handler/PadMessageHandler.js');
+    const padMessageHandler = require('ep_etherpad-lite/node/handler/PadMessageHandler');
     const payload = await buildPayload(message);
 
     const msg = {

pad-select-server.js

@@ -16,7 +16,7 @@ const PLUGIN_NAME_RE = /^ep_[a-z0-9_]+$/;
 let padOptionsPluginPassthrough = false;
 try {
   // eslint-disable-next-line global-require
-  const caps = require('ep_etherpad-lite/node/utils/PluginCapabilities.js');
+  const caps = require('ep_etherpad-lite/node/utils/PluginCapabilities');
   padOptionsPluginPassthrough = caps && caps.padOptionsPluginPassthrough === true;
 } catch (_e) { /* older core — leave as false */ }
 

pad-toggle-server.js

@@ -22,7 +22,7 @@ try {
   // and throws on older cores. Server-only: this file is never bundled for
   // the browser, so esbuild's static analysis does not run here.
   // eslint-disable-next-line global-require
-  const caps = require('ep_etherpad-lite/node/utils/PluginCapabilities.js');
+  const caps = require('ep_etherpad-lite/node/utils/PluginCapabilities');
   padOptionsPluginPassthrough = caps && caps.padOptionsPluginPassthrough === true;
 } catch (_e) { /* older core — leave as false */ }
 

settings-toggle.js

@@ -1,7 +1,7 @@
 'use strict';
 
 const eejs = require('ep_etherpad-lite/node/eejs');
-const settings = require('ep_etherpad-lite/node/utils/Settings.js');
+const settings = require('ep_etherpad-lite/node/utils/Settings');
 
 const createSettingsToggle = (config) => {
   const {