Adds extract_tables_with_structure_auto_mem (Rust) /
extractTablesWithStructureAuto (napi). Returns
TableExtractionResult { markdown, fallback_reason } per input.
The wrapper runs the existing TSR-hybrid path then checks the
resulting cells for two known SLANet detection pathologies:
* phantom_empty_row: empty row sandwiched between non-empty rows
(cheap, cell-metadata only).
* multi_row_in_cell: re-reads PDF text items, flags any cell whose
contained items span >1.3× either the smallest cell height or
the tallest contained item height. Catches the FNBO failure mode
where a tall TSR cell absorbs two adjacent PDF rows.
When either fires, extract_tables_in_regions_mem runs over the same
crop bbox and its markdown replaces the TSR markdown.
fallback_reason carries the diagnostic label so callers can emit
metrics and watch each pathology independently.
Validated on FNBO branches PDF page 1 (Kansas region):
- TSR-only: merges Shawnee into BVP, wrong census tract on Sonoma.
- Auto fallback (phantom_empty_row): each row separate, correct tracts.
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>