Add new solver setting CUOPT_MIP_PROBING and separate it from presolve

[akifcorduk]

Add CUOPT_MIP_PROBING setting (default true) to let users disable the probing-cache step of cuOpt's internal MIP presolve without disabling the rest of presolve. Existing CUOPT_PRESOLVE=0 still turns the whole pipeline off, so CUOPT_MIP_PROBING only matters when presolve is otherwise enabled.

[coderabbitai]

📝 Walkthrough

Walkthrough

Adds a new probing boolean to MIP solver settings (default true) to control the internal probing-cache step during MIP presolve; the change includes constant and struct additions, protobuf mapping, parameter registration, runtime checks to skip probing, and documentation/Python schema updates.

Changes

Probing Parameter Addition

Layer / File(s)	Summary
Parameter declaration and type definition cpp/include/cuopt/linear_programming/constants.h, cpp/include/cuopt/linear_programming/mip/solver_settings.hpp	Adds CUOPT_MIP_PROBING constant and probing boolean field (default true) to MIP solver settings with inline documentation about presolve interaction.
Protobuf message and C++ mapping cpp/src/grpc/cuopt_remote.proto, cpp/src/grpc/grpc_settings_mapper.cpp	Adds bool probing = 29 to MIPSolverSettings and wires bidirectional mapping in map_mip_settings_to_proto and map_proto_to_mip_settings.
Parameter registration and runtime enforcement cpp/src/math_optimization/solver_settings.cu, cpp/src/mip_heuristics/diversity/diversity_manager.cu	Registers CUOPT_MIP_PROBING in solver settings (bound to mip_settings.probing, default true) and honors context.settings.probing in run_presolve to skip the probing-cache step when false.
Documentation and Python integration docs/cuopt/source/cuopt-c/lp-qp-milp/lp-qp-milp-c-api.rst, docs/cuopt/source/lp-qp-milp-settings.rst, python/cuopt_server/cuopt_server/utils/linear_programming/data_definition.py	Adds C API parameter constant doc entry, inserts a "Probing" subsection in settings docs, and exposes optional mip_probing in Python SolverConfig.

🎯 3 (Moderate) | ⏱️ ~20 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title accurately describes the main change: adding a new CUOPT_MIP_PROBING solver setting that separates probing control from the presolve setting.
Description check	✅ Passed	The pull request description accurately describes the changeset: adding a new CUOPT_MIP_PROBING setting (default true) to let users disable the probing-cache step during MIP presolve while keeping other presolve steps enabled.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@cpp/src/grpc/cuopt_remote.proto`:
- Around line 204-205: The plain proto3 bool field `probing` cannot express
presence so older clients default it to false; change the proto declaration for
`probing` to be presence-aware (use proto3 "optional bool probing = 29;" or a
google.protobuf.BoolValue wrapper) and then modify grpc_settings_mapper.cpp to
only assign into `settings.probing` when the field is present by checking
`pb_settings.has_probing()` before doing the assignment (i.e., call
`pb_settings.probing()` only inside the presence check) so older clients
preserve the intended default-true behavior.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

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📥 Commits

Reviewing files that changed from the base of the PR and between 785f148 and 0f72a14.

📒 Files selected for processing (9)

• cpp/include/cuopt/linear_programming/constants.h
• cpp/include/cuopt/linear_programming/mip/solver_settings.hpp
• cpp/src/grpc/cuopt_remote.proto
• cpp/src/grpc/grpc_settings_mapper.cpp
• cpp/src/math_optimization/solver_settings.cu
• cpp/src/mip_heuristics/diversity/diversity_manager.cu
• docs/cuopt/source/cuopt-c/lp-qp-milp/lp-qp-milp-c-api.rst
• docs/cuopt/source/lp-qp-milp-settings.rst
• python/cuopt_server/cuopt_server/utils/linear_programming/data_definition.py

[chris-maes]

CUOPT_PROBING -> CUOPT_MIP_PROBING

[coderabbitai]

🧹 Nitpick comments (1)

cpp/src/math_optimization/solver_settings.cu (1)

177-177: ⚡ Quick win

Add an inline description for the new probing parameter.

CUOPT_MIP_PROBING is an algorithm parameter, but this registration omits the description field that your parameter dump/help path uses.

Suggested patch

-    {CUOPT_MIP_PROBING, &mip_settings.probing, true},
+    {CUOPT_MIP_PROBING,
+     &mip_settings.probing,
+     true,
+     "enable probing-cache step in cuOpt internal MIP presolve (ignored when presolve is off)"},

As per coding guidelines, "Flag missing documentation for numerical tolerances and algorithm parameters".

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@cpp/src/math_optimization/solver_settings.cu` at line 177, The registration
entry for the new algorithm parameter CUOPT_MIP_PROBING (which references
mip_settings.probing) is missing the human-readable description used by the
parameter dump/help path; update the registration tuple/struct where
CUOPT_MIP_PROBING is added so it includes an appropriate inline description
string (briefly describing what probing does and valid values/default behavior)
alongside the existing name, pointer, and enabled flag so the help/dump output
documents the parameter correctly.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@cpp/src/math_optimization/solver_settings.cu`:
- Line 177: The registration entry for the new algorithm parameter
CUOPT_MIP_PROBING (which references mip_settings.probing) is missing the
human-readable description used by the parameter dump/help path; update the
registration tuple/struct where CUOPT_MIP_PROBING is added so it includes an
appropriate inline description string (briefly describing what probing does and
valid values/default behavior) alongside the existing name, pointer, and enabled
flag so the help/dump output documents the parameter correctly.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Enterprise

Run ID: 2844f9f5-8c3e-4cb0-9899-214b920ce69e

📥 Commits

Reviewing files that changed from the base of the PR and between 0f72a14 and 286c235.

📒 Files selected for processing (6)

• cpp/include/cuopt/linear_programming/constants.h
• cpp/src/math_optimization/solver_settings.cu
• cpp/src/mip_heuristics/diversity/diversity_manager.cu
• docs/cuopt/source/cuopt-c/lp-qp-milp/lp-qp-milp-c-api.rst
• docs/cuopt/source/lp-qp-milp-settings.rst
• python/cuopt_server/cuopt_server/utils/linear_programming/data_definition.py

[chris-maes]

LGTM. Thanks for adding this setting @akifcorduk

[rgsl888prabhu]

Approving all other changes, not completely sure about GRPC part, but mostly looks good.

[rg20]

/merge