Add Docker-based reproducible build; remove PuLP, solve ILPs with Gur…

[edwjchen]

Reproducibility / Docker

• Add Dockerfile (python:3.11-slim + build-essential, clang/lld, cmake, ninja, golang) and .dockerignore; non-root build via USER_ID/GROUP_ID.
• Add scripts/reproduce.sh with quick/full/execute modes; execute runs a compiled MLIR through the Lattigo backend (plaintext or FHE).
• Add scripts/setup_dependencies.sh to build the Dacapo/Hecate frontend and Lattigo backend on demand (keeps the image lean).
• Add scripts/gurobi_license_sweep.sh to classify which benchmark configs fit the bundled size-limited Gurobi license vs. need a full license.
• run_orbit.py: add --threads passthrough and propagate optimizer exit code.
• .gitignore: ignore .deps/ and repro_results/.
• README: Docker build/run instructions, solver/license notes, and the optional end-to-end execution + Dacapo data-gen flow.

Solver: drop PuLP/CBC, use Gurobi only

• ilp_core.py: remove the PuLP code path (var pool, safe-name helpers, *_pulp builders, _solve_ilp_pulp) and solve ILPs directly with Gurobi.
• Remove the --ilp-solver flag and ilp_solver param plumbing across optimizer.py, run_orbit.py, and params.py.
• requirements.txt: drop pulp.
• Tests: drop the PuLP-specific test, update CLI/param/integration tests to the Gurobi-only path.