Wire the shader census into the run report (half done)

The CLI half is done: orbistoun-cli shaders <dir> ranks what blocks translation across a corpus, as a thin shim over orbistoun-shader::report.

The run-report half is not. The census numbers do not go through the diff-against-previous machinery, so "did that change unblock anything?" is answered by reading two outputs side by side rather than by a verdict - which is exactly the thing the import side stopped doing at D047.