feat: jit(fit_from) round-trip for Delaunay source + MGE lens

[Jammy2211]

Overview

Extend Path A (jax.jit-wrapped analysis.fit_from) to FitImaging with a Delaunay pixelization source AND an MGE lens bulge, so that jax.jit(analysis.fit_from)(instance) returns a fully-populated FitImaging matching the NumPy-path scalar. This is the intersection of fit_imaging_pytree_delaunay (#453) and the MGE PoC.

Plan

• Scaffold delaunay_mge_pytree.py combining MGE bulge + Isothermal + ExternalShear lens with Hilbert image-mesh + Delaunay pixelization source (single pixelization, exercises the narrow fallback from PyAutoGalaxy#361).
• Run under use_jax=True; iterate any unregistered types.
• Expected: no new registrations if predecessors landed clean.

Detailed implementation plan

Affected Repositories

• autolens_workspace_test (primary)
• PyAutoLens, PyAutoGalaxy, PyAutoArray — only if unregistered types surface

Branch Survey

Repository	Current Branch	Dirty?
PyAutoLens	main	clean
PyAutoGalaxy	main	clean
PyAutoArray	main	clean
autolens_workspace_test	main	clean

Suggested branch: feature/fit-imaging-pytree-delaunay-mge
Worktree root: ~/Code/PyAutoLabs-wt/fit-imaging-pytree-delaunay-mge/

Key Files

• autolens_workspace_test/scripts/jax_likelihood_functions/imaging/delaunay_mge_pytree.py — new

Original Prompt

See admin_jammy/prompt/issued/fit_imaging_pytree_delaunay_mge.md.

[Jammy2211]

Shipped — 2026-04-19

PRs

• add delaunay_mge_pytree.py: jit(fit_from) for Delaunay source + MGE lens autolens_workspace_test#43

Summary

Workspace-only PR. MGE bulge + Isothermal lens + Hilbert image-mesh + Delaunay-pixelization source passed on first run with no new library registrations. Narrow single-entry galaxy_image_plane_mesh_grid_dict fallback from PyAutoGalaxy#361 fires correctly for this single-pixelization model.

Session Notes

• The galaxy_pytree_token.md follow-up remains required only for multi-pixelization Delaunay/Hilbert variants, which are not among the remaining queued prompts.
• NumPy 359.638 vs JIT 359.638 — agreement well within rtol=1e-4.

[Jammy2211]

Shipped via PyAutoLabs/autolens_workspace_test#43. Closing.