feat(reporting): add one-plate nest report PDF library slice

Add OpenNest.Reporting (net8.0, PDFsharp-MigraDoc 6.2.4) with a detached
report snapshot and a PDF writer for an empty/demand-only job or a single
plate layout: Letter portrait summary with vector part thumbnails and a
landscape plate page with a vector sheet diagram, both with Page X of Y.

- Snapshot uses reference identity for document-local R### IDs, recounts
  nested quantities from placements x copies with checked wide integers,
  excludes cutoffs from accounting, and retains no live domain objects.
- Geometry keeps Cut/Display material paths, drops rapid/scribe/lead paths,
  preserves native arcs, holes and intentional tab gaps, and rejects
  malformed programs with plate/part identification.
- Open contours and cutoffs are stroked per contour so PDFsharp cannot join
  a tab gap to the next contour.
- Bundled DejaVu Sans via a custom resolver (including MigraDoc's error
  font); unsupported text fails with the field and code point.
- Layouts beyond this slice (multiple plates, page overflow, labels that
  do not fit) fail with NotSupportedException before the destination is
  replaced; output is rendered to a temporary sibling and moved atomically.

OpenNest.Tests/OpenNest.Tests.csproj

@@ -29,6 +29,7 @@
     <ProjectReference Include="..\OpenNest.Core\OpenNest.Core.csproj" />
     <ProjectReference Include="..\OpenNest.Engine\OpenNest.Engine.csproj" />
     <ProjectReference Include="..\OpenNest.IO\OpenNest.IO.csproj" />
+    <ProjectReference Include="..\OpenNest.Reporting\OpenNest.Reporting.csproj" />
     <ProjectReference Include="..\Posts\OpenNest.Posts.Cincinnati\OpenNest.Posts.Cincinnati.csproj" />
     <ProjectReference Include="..\Posts\OpenNest.Posts.CincinnatiCIFiber\OpenNest.Posts.CincinnatiCIFiber.csproj" />
     <ProjectReference Include="..\Posts\OpenNest.Posts.GravographIS\OpenNest.Posts.GravographIS.csproj" />