feat(cardex): image-search harvester + genre-diverse character library

Grow the hh card-art library so common VM types stop reusing one portrait.

- scripts/imgharvest.py: keyless DuckDuckGo image-search harvester — downloads
  many stills per character and runs them through charvest's crop/quality/dedup
  pipeline (static art crops far cleaner than motion-blurred video frames).
- scripts/harvest_roster.sh: batch roster (Pokemon/Digimon/Yu-Gi-Oh) sized to
  the live VM card types. Library now 37 characters / 99 portraits.
- charvest: top-anchor the head+shoulders crop for tall full-body art so faces
  are no longer clipped.

chardex matcher — stop same-type VMs collapsing onto a single face:
- fold a per-(VM,character) hash jitter INTO the score, not just a tie-break
- diminishing returns on extra type matches so a strong single-type face can
  compete with a dual-type one
- halve tier affinity and cap the keyword bonus
- stop-word rarity/boilerplate words that were polluting keyword overlap
Result: 20 distinct faces across the library. The one remaining cluster
(Sigilyph on the Psychic/Flying recon-scanner VMs) is coherent purpose-
matching — a scanner-themed bird on the scanner VMs — not a bug.

NOTE: assets/characters/ are third-party franchise IP with NO established reuse
license — quarantined, internal WIP only, do not distribute/merge/publish
(licensing record in docs/character-art-licensing.md).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

scripts/harvest_roster.sh

@@ -0,0 +1,48 @@
+#!/usr/bin/env bash
+# Batch-harvest a genre-diverse character roster for the hh card-art library.
+# Covers the card types the live VM registry actually uses (Normal/Psychic/
+# Flying/Steel/Ghost/Electric/Fire) with MULTIPLE distinct faces per type so
+# cards stop sharing a portrait. Mixes Pokémon, Digimon and Yu-Gi-Oh.
+set -u
+cd "$(dirname "$0")/.."
+PY=python3
+
+# NAME | QUERY | ELEMENTS | TIER | KEYWORDS | CREDIT
+ROSTER=$(cat <<'EOF'
+Snorlax|Snorlax pokemon official artwork|Normal|Uncommon|heavy sleepy tank bulk immovable|Pokemon
+Eevee|Eevee pokemon official artwork|Normal|Common|adaptable versatile cute evolving|Pokemon
+Ditto|Ditto pokemon official artwork|Normal|Common|shapeshifter clone transform copy mimic|Pokemon
+Regigigas|Regigigas pokemon official artwork|Normal|Legendary|titan colossus ancient golem legendary|Pokemon
+Agumon|Agumon digimon render|Normal Fire|Common|rookie brave dinosaur partner plucky|Digimon
+Yugi|Yugi Muto Yu-Gi-Oh character art|Normal|Rare|duelist strategist heart cards hero|Yu-Gi-Oh
+Mew|Mew pokemon official artwork|Psychic|Legendary|mythical origin playful ancestor rare|Pokemon
+Alakazam|Alakazam pokemon official artwork|Psychic|Epic|intellect genius spoons brain calculate|Pokemon
+Espeon|Espeon pokemon official artwork|Psychic|Rare|foresight elegant sun intuition graceful|Pokemon
+DarkMagician|Dark Magician Yu-Gi-Oh artwork|Psychic Ghost|Epic|spellcaster arcane sorcerer magic conjure|Yu-Gi-Oh
+Rayquaza|Rayquaza pokemon official artwork|Flying Dragon|Legendary|sky serpent ozone legendary skybound|Pokemon
+Pidgeot|Pidgeot pokemon official artwork|Flying Normal|Rare|swift raptor scout recon aerial|Pokemon
+Lugia|Lugia pokemon official artwork|Flying Psychic|Legendary|guardian sea storm diving legendary|Pokemon
+BlueEyes|Blue-Eyes White Dragon Yu-Gi-Oh artwork|Flying Dragon|Legendary|destruction white legendary burst power|Yu-Gi-Oh
+Metagross|Metagross pokemon official artwork|Steel Psychic|Epic|supercomputer armored quad calculating fortress|Pokemon
+Aggron|Aggron pokemon official artwork|Steel Rock|Rare|iron fortress defense armored tank|Pokemon
+MetalGreymon|MetalGreymon digimon render|Steel|Epic|cyborg missiles armored machine upgraded|Digimon
+Dusknoir|Dusknoir pokemon official artwork|Ghost|Epic|reaper spectral netherworld grim sentinel|Pokemon
+Chandelure|Chandelure pokemon official artwork|Ghost Fire|Rare|spectral flame haunting lantern eerie|Pokemon
+Zapdos|Zapdos pokemon official artwork|Electric Flying|Legendary|thunder storm legendary charged bolt|Pokemon
+Luxray|Luxray pokemon official artwork|Electric|Rare|vision predator feline hunt piercing|Pokemon
+Blaziken|Blaziken pokemon official artwork|Fire|Epic|blazing martial striker kick fierce|Pokemon
+Greymon|Greymon digimon render|Fire|Rare|dinosaur nova blaze horn champion|Digimon
+EOF
+)
+
+n=0
+while IFS='|' read -r NAME QUERY ELEMENTS TIER KEYWORDS CREDIT; do
+  [ -z "$NAME" ] && continue
+  n=$((n+1))
+  echo "== [$n] $NAME ($ELEMENTS / $TIER) =="
+  $PY scripts/imgharvest.py "$QUERY" \
+      --name "$NAME" --element $ELEMENTS --tier "$TIER" \
+      --keywords $KEYWORDS --credit "$CREDIT" --max 3 --candidates 18 \
+    || echo "  ! $NAME failed"
+done <<< "$ROSTER"
+echo "ALL DONE ($n characters)"