Materialize cross-domain links in committed datasets

Commit c95f02d added the cross-domain mapping code (MP -> electoral
constituency, legal entity -> registered admin unit) but shipped pipeline
code only, without regenerating datasets/current/. The committed snapshots
therefore lacked the links, and the two example queries that rely on them
returned nothing.

Regenerate the affected domains (make -C etl/seimas all, make -C
etl/legal-entities all) so the snapshots include:

- persons.trig: ltlod:electoralDistrict from each single-member seat tenure
  to constituencies/ (74 links across 71 districts); plus fresh members-feed
  data (a membership end date, new tenure records).
- constituencies/constituencies.trig: 71 single-member electoral districts
  (apygardos) parsed from the members feed (new container).
- institutions.trig: the SEMIC registered-office chain org:hasRegisteredSite
  -> org:Site -> org:siteAddress -> locn:Address -> locn:adminUnit into the
  admin-units hierarchy (2507 offices resolved).
- EXAMPLES.md: the previously-empty "Seimo nariai pagal apygardą" and
  "Įstaigos pagal savivaldybę" result tables, re-rendered.

Both datasets validate (riot + SHACL). The large TriG line churn is arq
CONSTRUCT output reordering, not semantic change (persons.trig delta is
+78/-1 quads by sorted N-Quads).

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

Author: namedgraph