`CREATE EXTENSION ruvector` was failing when the extension was built
without optional feature flags (solver, math-distances, tda,
attention-extended, sona-learning, domain-expansion) because the SQL
migration unconditionally registered C functions whose symbols didn't
exist in the compiled .so file.
Wrap all 6 optional-feature sections in DO $ BEGIN ... EXCEPTION WHEN
OTHERS THEN RAISE NOTICE ... END $ blocks so PostgreSQL gracefully skips
missing C function symbols and logs an informational notice instead of
aborting the entire extension load.
Fixes#325
Co-authored-by: ruvnet <ruvnet@gmail.com>
