elp(comprehend): el-native comprehension parser + SACRED polarity end-to-end

PIECE 1 — greenfield el-native parser (comprehend.el), spaCy-free:
- text -> meaning-spec via invertible English morphology (the realizer's own
  irregular table run BACKWARD) + a deterministic clause grammar (subject/verb
  boundary, roles, ditransitive iobj, PP adjuncts, subordination, coordination).
- NEGATION IS SACRED: explicit polarity field, always present, cross-lingual
  lexeme set; standalone neg adverbs (never) captured separately.
- WSD by deterministic syntactic position over a fixed sense inventory
  (flies->fly, like->comparison, saw->see); engram nearest-region is the
  documented runtime upgrade hook (no external model).

Polarity threaded through the whole el contract (was previously dropped at the
boundary): realizer.el realize_lang honors polarity (English do-support /
adverbial / copular negation; generic preverbal negator for es/pt/ca/it/fr/de/ro)
and places iobj; elp.el build_form_from_json carries polarity/neg_word/iobj
across JSON; morphology.el gains 'fight'.

Acceptance (native el telephone test, comprehend_gate.el): on the 5 gate
sentences polarity PRESERVED 5/5 and EXTRACTED 5/5 through parse->realize->
re-parse; 4/5 byte-identical. Built bounded (elc rc=0, cc rc=0).

elp/src/morphology.el

@@ -250,6 +250,7 @@ fn en_irregular_verb(base: String) -> [String] {
     if str_eq(base, "cut")     { let r: [String] = ["cut",    "cuts",  "cut",    "cut",     "cutting"];  return r }
     if str_eq(base, "set")     { let r: [String] = ["set",    "sets",  "set",    "set",     "setting"];  return r }
     if str_eq(base, "hit")     { let r: [String] = ["hit",    "hits",  "hit",    "hit",     "hitting"];  return r }
+    if str_eq(base, "fight")   { let r: [String] = ["fight",  "fights","fought", "fought",  "fighting"]; return r }
     return empty
 }