merge: bring main's part-assembly-edit feature into the FreeLand branch

feat(edit): parts fuse and redistribute instead of stacking

feat(edit): replace small-model selector with keyword + parametric assembler

refactor(parts): split catalog into parts_data.py + add category schema

feat(lab): FreeLand from-scratch entry + Random, draft creatures, canvas/nav polish

feat(runtime): selector->assembler edit path with freeform fallback

feat(parts/assembler): catalog parts + deterministic anchor placement

test+docs: repair edit_creature 4-tuple test; wiki for canvas + one-call tweak

merge: share lineage GIF + voxel build animation into main

feat(share): Quick Draw!-style lineage GIF share flow + voxel build animation

feat(bench): big 3D scenes + Gemma-suggested hint bubbles in a halo arc

fix(ui): game-style Splice Bench — chips flank the model, centered & aligned

feat(compendium): data module + report tool + first 12 creatures

feat(freeform): route the whole main flow through the freeform path

feat(freeform): steer one dominant body colour + accents in prompts

feat(freeform): add biped/bird/round/serpent reference exemplars

feat(tools): same-model overwrite on eval merge

feat(tools): add voxel-model-eval harness + skill

feat: freeform voxel generation (Gemma 4 12B) + freeform breeding

feat(lab): add splice-bench render + chip helpers

fix: AI tweak no-op on the real model when the edit is empty

feat: Build Buddy — voxel pet fusion (AI genetics engine)