refactor(tooling): T-1273 — the Blender carve-out, and a guard that keeps it carved

35 payloads move to tooling/scripts/blender/ and stay outside package scope.
They run under Blender's bundled Python, which cannot see the repo venv, so
they physically cannot import tooling.core — holding them to the D-263 contract
would either fail the gate forever or force the contract to be weakened for
everyone, and the second is how a gate stops meaning anything.

Count verified by import rather than filename: 33 import bpy/bmesh directly,
and the two that do not are still payloads per their own usage lines.
garment-fit/make_logo.py is the one genuine non-payload and stays for T-1290.

The bash wrapper is retired rather than kept. Keeping it would have put the
install-resolution logic in two places, which is the duplication T-1286 had
just finished collapsing three copies of. domains/blender/service.py owns the
decisions — resolve_blender (native beats flatpak, ordering preserved),
resolve_payload, absolutise — and only run_payload performs. test_blender.py
pins all of them without launching Blender, which matters here more than
usual: the thing being launched is a 200 MB GUI application that writes GLBs.

`reach blender run` takes a registered payload name OR a path to any script,
because the wrapper served both — the spikes and the glb-gen skill hand it
one-off scripts of their own. An unknown name enumerates all 35 and exits 2.

The exclusion now defends itself. check_carve_out_stays_carved fails if
`scripts` is added to PACKAGE_ROOTS, if the payload directory empties (an empty
exclusion proves nothing), or if an __init__.py appears there (which would make
the payloads importable — the coupling the carve-out exists to prevent). All
three arms mutation-proved.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Makefile

@@ -310,6 +310,10 @@ test-tooling:
 	@mkdir -p .cache
 	@$(VENV_PY) tooling/test_jobs.py 2> .cache/test-tooling-jobs.log || \
 		{ echo "  FAIL: jobs service — log follows:"; cat .cache/test-tooling-jobs.log; exit 1; }
+	@echo "  [test-tooling] reach blender carve-out decisions (T-1273)..."
+	@mkdir -p .cache
+	@$(VENV_PY) tooling/test_blender.py 2> .cache/test-tooling-blender.log || \
+		{ echo "  FAIL: blender decisions — log follows:"; cat .cache/test-tooling-blender.log; exit 1; }
 	@echo "  [test-tooling] reach dev environment decisions (T-1286)..."
 	@mkdir -p .cache
 	@$(VENV_PY) tooling/test_environment.py 2> .cache/test-tooling-environment.log || \