[WEB + CLSI] Download as docx file feature (#32851)

* using CLSI logic for fetching the project contents and skip the .zip export

* Use unique conversion directory for project-to-docx export to avoid corrupting the shared compile
  directory when a compile runs concurrently

* Remove X-Accel-Buffering header — not needed as CLSI does not run behind nginx

* moving log before sending the data

* Return CLSI stream directly instead of buffering to disk on web

  Previously convertProjectToDocx wrote the CLSI response to a temp file
  on disk, then the controller read it back to stream to the client.
  Now the stream is returned directly and piped to the response,
  avoiding unnecessary disk I/O on the web server.

* Use href redirect for docx export instead of fetching blob into memory

* making functions and files more generic so they can be used in future for other documents exports as well

* adding export-docx split test

* adding unit tests

* adding cypress E2E test

* format:fix

* renaming the route to download from convert

* adding new icon for export docx button

* format:fix

* remove unused showExportDocumentErrorToast export and adding guard against invalid Content-Length header from CLSI

* format:fix

* refactor(clsi): move promisify(parse) into RequestParser

* refactor: generic conversion endpoint with type as route
  param

* refactor: use type→extension map for validated conversion types

* refactor(clsi): remove --standalone flag and fix rejection test

* fixing the href in cypress test

* renaming function

* adding type to Metrics.inc

* fix: rename exportProjectDocument, add WithLock wrapper and metrics type label

* format:fix

* fix: hide docx export from anonymous users and add WithLock wrapper

* format fix

* remove redundant Content-Length validation from DocumentConversionManager

* format:fix

* removing trailing icon

GitOrigin-RevId: e9764fefac2c4b625d23be9e942ea4a8b283c70d

services/clsi/app/js/ConversionManager.js

@@ -94,8 +94,77 @@ async function convertDocxToLaTeX(conversionId, conversionDir, inputPath) {
   return Path.join(conversionDir, outputName)
 }
 
+async function convertLaTeXToDocumentInDirWithLock(
+  conversionId,
+  compileDir,
+  rootDocPath,
+  type,
+  extension
+) {
+  const lock = LockManager.acquire(compileDir)
+  try {
+    return await convertLaTeXToDocumentInDir(
+      conversionId,
+      compileDir,
+      rootDocPath,
+      type,
+      extension
+    )
+  } finally {
+    lock.release()
+  }
+}
+
+async function convertLaTeXToDocumentInDir(
+  conversionId,
+  compileDir,
+  rootDocPath = 'main.tex',
+  type,
+  extension
+) {
+  const outputName = crypto.randomUUID() + '.' + extension
+  const timeoutMs = Settings.conversionTimeoutSeconds * 1000
+
+  logger.debug(
+    { compileDir, rootDocPath, type },
+    'running pandoc latex-to-document in compile dir'
+  )
+
+  const { exitCode, stdout, stderr } = await CommandRunner.promises.run(
+    conversionId,
+    [
+      'pandoc',
+      rootDocPath,
+      '--output',
+      outputName,
+      '--from',
+      'latex',
+      '--to',
+      type,
+      '--resource-path=.',
+    ],
+    compileDir,
+    Settings.pandocImage,
+    timeoutMs,
+    {},
+    'conversions'
+  )
+
+  if (exitCode !== 0) {
+    throw new OError('pandoc latex-to-document conversion failed', {
+      type,
+      exitCode,
+      stdout,
+      stderr,
+    })
+  }
+
+  return Path.join(compileDir, outputName)
+}
+
 export default {
   promises: {
     convertDocxToLaTeXWithLock,
+    convertLaTeXToDocumentInDirWithLock,
   },
 }