Fix Quarto compile pipeline: install, logs, template, draft mode

Dockerfile-base: remove TeX Live (no longer needed), install Quarto
  1.6.39 which bundles Typst for PDF output. This was the root cause
  of all compile failures — the server-ce monolith never had Quarto.

QuartoRunner: run quarto via /bin/sh so stderr is merged into stdout
  with 2>&1; write combined output to output.log (not output.stdout)
  so the PDF-preview log panel picks it up and shows raw output.
  Also write the log on error so failures are always visible.

CompileManager: guard DraftModeManager behind an isLatexFile check —
  injecting LaTeX preamble commands into a .qmd file corrupts it and
  causes a guaranteed compile failure when draft mode is requested.

ProjectCreationHandler + mainbasic.qmd: new projects now create
  main.qmd with a minimal Quarto/Typst frontmatter instead of the
  LaTeX main.tex; _createRootDoc names the file main.qmd accordingly.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

services/web/app/src/Features/Project/ProjectCreationHandler.mjs

@@ -88,7 +88,7 @@ async function createProjectFromSnippet(ownerId, projectName, docLines) {
 async function createBasicProject(ownerId, projectName) {
   const project = await _createBlankProject(ownerId, projectName)
 
-  const docLines = await _buildTemplate('mainbasic.tex', ownerId, projectName)
+  const docLines = await _buildTemplate('mainbasic.qmd', ownerId, projectName)
   await _createRootDoc(project, ownerId, docLines)
 
   AnalyticsManager.recordEventForUserInBackground(ownerId, 'project-created', {
@@ -304,7 +304,7 @@ async function _createRootDoc(project, ownerId, docLines) {
     const { doc } = await ProjectEntityUpdateHandler.promises.addDoc(
       project._id,
       project.rootFolder[0]._id,
-      'main.tex',
+      'main.qmd',
       docLines,
       ownerId,
       null