phase 5: edge transforms, soleprint-ui rename, infra fixes

- pipeline edge transforms: stages can declare accepted_transforms,
  edges carry a transform dict, runner injects per-stage and nodes
  apply (e.g. invert_mask before edge detection); editable from UI
  via PUT /config/edge-transform
- rename mpr-ui-framework -> soleprint-ui (now an external package
  synced via .spr from /home/mariano/wdir/spr); add @vue-flow/core
  and uplot to detection-app so linked package resolves them
- Tiltfile guards kubectl context, k8s commands pin --context kind-mpr
- kind-config: gateway on hostPort 30080 (Caddy fronts mpr.local.ar)
- modelgen: pyproject.toml, .spr marker, dict default_factory support

modelgen/pyproject.toml

@@ -0,0 +1,16 @@
+[build-system]
+requires = ["setuptools>=68.0"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "soleprint-modelgen"
+version = "0.2.0"
+description = "Multi-source, multi-target model code generator"
+requires-python = ">=3.10"
+dependencies = []
+
+[project.scripts]
+modelgen = "modelgen.__main__:main"
+
+[tool.setuptools.packages.find]
+include = ["modelgen*"]