tulpa 0.0.135

• A prior block missing its required fields now errors instead of segfaulting
  the session (#299). Each .NL_REGISTRY entry declares, per
  dispatch path, the fields its converter indexes; the shared
  .nl_check_block_fields() checks them at the four boundaries that feed the
  kernels (.nl_dispatch(), .nl_block_axis_grid(),
  .nl_block_spec_for_cpp(), .joint_block_spec_for_cpp(), plus the
  single-block joint packer). A block naming a field wrongly -- a typo, a stale
  name after a rename, a block copied from a different family -- used to reach
  the C++ side as a zero-length vector, which the kernels index with no bounds
  check; it now raises
  prior block 'icar' is missing required field(s): spatial_idx, adj_row_ptr, adj_col_idx, n_neighbors. A field present but empty counts as missing, since
  that is the same out-of-bounds read. The per-branch presence checks that had
  accumulated in the joint converter are replaced by the shared one, so the
  declaration is the single source of truth; test-nl-required-fields.R walks
  every registry entry on every declared path dropping one field at a time, and
  lints both converters' sources so a field read unconditionally by a branch but
  left undeclared fails the suite.