Remove sample identities from the repository; document the rule

Datasets may be confidential; sample names and measured unit cells committed to
the repo can leak outside the group working on them. Scrub existing occurrences
and add a "No sample identities in the repository" section to CLAUDE.md
(forbidden: sample/dataset names, internal codes, measured cells tied to a
sample; fine: space group / lattice / twinning descriptors).

- Comments: replace internal dataset codes and protein names with the
  crystallographic situation they illustrate (centred vs pseudo-symmetric,
  holohedral, cubic, F-cubic/hexagonal, ...).
- Docs: same, in the analysis/writer/stream references and example configs.
- Tests: rename sample-named identifiers, TEST_CASE names, file prefixes and
  asserted labels to neutral crystallographic names (e.g. tetragonal_uc);
  behaviour unchanged. Reduce the CrystFEL reference PDB to a bare CRYST1 cell
  file (cell.pdb) and rename the reference data file.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tools/jfjoch_lite_perf_test.cpp

@@ -18,7 +18,7 @@ void print_usage(Logger &logger) {
     logger.Info("Options:");
     logger.Info("   -i<num>      Number of images");
     logger.Info("   -N<num>      Number of image processing threads (default: 8)");
-    logger.Info("   -F{<txt>}    Write file, optional parameter is name (default: lyso_lite_perf_test)");
+    logger.Info("   -F{<txt>}    Write file, optional parameter is name (default: lite_perf_test)");
     logger.Info("   -X<txt>      Indexing (none|fft|fftw|ffbidx), ffbidx is default");
     logger.Info("   -t<num>      Indexing thread pool size (default: 4)");
     logger.Info("   -f<num>      FFT indexing search vectors");
@@ -82,7 +82,7 @@ int main(int argc, char **argv) {
                 if (optarg)
                     filename = std::string(optarg);
                 else
-                    filename = "lyso_lite_perf_test";
+                    filename = "lite_perf_test";
                 break;
             case 'Q':
                 quick_integrate = true;