Support weighted maxsat

[AHartNtkn]

Add support for weighted maxsat and "must have" clauses.

• Modify src/cnf.rs to handle weighted CNF files and "must have" clauses.

  • Add weight field to CNFClause struct.
  • Add must_clause_weight field to CNFFormula struct.
  • Update parse_dimacs_format to parse weight lines and assign weights to clauses.
  • Update apply_variable_mapping and normalize_variables to handle weights.
  • Update to_dimacs_format to include weight lines if present.

• Modify src/main.rs to keep track of the best solution found within a specific amount of time.

  • Add time_limit option to Opts, StochOpts, and InterhOpts structs.
  • Add time limit handling in solve and batch functions.
  • Track the best solution and score during the simulation loop.
  • Return the best solution found within the time limit.

---

For more details, open the Copilot Workspace session.