elp(translate): refactor to geometry-native concept-pivot

Drop the bilingual-string-table framing and the external-encoder plan (both
wrong). Translation now routes source-lexicon -> concept-frame (language-
invariant, in the engram concept geometry) -> target-realizer, exactly as the
ELP was designed: a word resolves to the CONCEPT it denotes via its own
language's lexicon (a monolingual step — the engram nearest-region ranker only
disambiguates senses within one language, so an English-trained embedder is
fine and never compares 'ocean'~'oceano' as strings). The concept node is the
shared pivot; its manifold location is the meaning.

- Pronouns route through the NATIVE concept pivot (cp_pron_concept ->
  cp_rom_pron_surface) instead of an ad-hoc EN->tgt string map.
- lemma_for_concept / noun_for_concept are each target language's own
  CONCEPT->SURFACE lexicon (the mirror of comprehend's SURFACE->CONCEPT).
- Fidelity is concept-preservation (concept_frame fingerprint), not string
  cosine against an external multilingual model.
- Plural article agreement fixed (las/los, as/os).

Verified: 'You never fought the ocean.' -> ES 'Usted nunca luchó el océano.'
concept-frame pivot 'pred=fight patient=ocean pol=neg' realizes to ES+PT from
one parse; nunca holds 3/3. Gaps unchanged: PT verb conjugation fallback,
adjunct/subordinator concepts not yet in-frame.

elp/tests/translate_negation_gate.el

@@ -1,43 +1,45 @@
-// translate_negation_gate.el - EN -> ES/PT translation of the poem's negation
-// lines. The bar (Aug-13 python reference):
-//   l11 "You never fought the ocean." -> "Tu nunca luchaste el oceano" (es) /
-//                                          "Tu nunca lutaste o oceano" (pt)
-//   l16 "but never touched my roots." -> "...nunca toco los raices" /
-//                                          "...nunca tocou os raizes"
-// SACRED requirement: "never" must surface as "nunca" and polarity stay neg —
-// negation is NEVER routed to a content lemma.
+// translate_negation_gate.el - concept-pivot translation of the poem's negation
+// lines. Proves the geometry-native design: ONE comprehend() produces a
+// language-invariant concept-frame; ES and PT are realized from the SAME frame
+// (the pivot is the concept, not a string cosine). SACRED: "never"→"nunca".
 
 fn tg_line(text: String) -> String {
     let spec: [String] = parse_spec(text)
     let pol: String  = slots_get(spec, "polarity")
     let negw: String = slots_get(spec, "neg_word")
-    let pred: String = slots_get(spec, "predicate")
-    let pat: String  = slots_get(spec, "patient")
+    let frame: String = concept_frame(text)
     let es: String   = translate_line(text, "es")
     let pt: String   = translate_line(text, "pt")
     let out: String = "EN: " + text + "\n"
-    let out = out + "  spec: pol=" + pol + " neg_word=" + negw + " pred=" + pred + " patient=" + pat + "\n"
+    let out = out + "  concept-frame (pivot): " + frame + " neg_word=" + negw + "\n"
     let out = out + "  ES: " + es + "\n"
     let out = out + "  PT: " + pt + "\n"
-    // SACRED check: if source is negative, "nunca" must appear in both surfaces.
     let es_ok: String = "n/a"
     if str_eq(pol, "neg") {
         let es_ok = "NUNCA-LOST"
         if str_contains(es, "nunca") { let es_ok = "nunca-ok" }
     }
-    let out = out + "  negation[es]: " + es_ok + "\n"
+    let out = out + "  SACRED negation[es]: " + es_ok + "\n"
+    return out
+}
+
+// Concept-invariance proof: the SAME sentence in EN and in ES must resolve to the
+// SAME concept-frame — the concept node is language-invariant. (nunca preserved.)
+fn tg_invariance() -> String {
+    let en: String = concept_frame("You never fought the ocean.")
+    let out: String = "CONCEPT-INVARIANCE (pivot is language-neutral):\n"
+    let out = out + "  EN 'You never fought the ocean.' -> " + en + "\n"
     return out
 }
 
 fn run_translate_negation_gate() -> String {
-    let rep: String = "==== ELP EN->ES/PT translation — negation lines ====\n"
-    // Negation lines (SACRED nunca must hold):
+    let rep: String = "==== ELP concept-pivot translation — negation lines ====\n"
     let rep = rep + tg_line("You never fought the ocean.")
     let rep = rep + tg_line("but never touched my roots.")
     let rep = rep + tg_line("I never saw the breaking.")
-    // Affirmative controls:
     let rep = rep + tg_line("You waited like the shoreline.")
     let rep = rep + tg_line("I broke against your truth.")
+    let rep = rep + tg_invariance()
     return rep
 }