tap/psm: geom boost

[gadfort]

Summary

Switch PSM and TAP to use the geom_boost converters instead of their own.

Type of Change

• Refactoring

Impact

Should be a no-op

Verification

• I have verified that the local build succeeds (./etc/Build.sh).
• I have run the relevant tests and they pass.
• My code follows the repository's formatting guidelines.
• I have signed my commits (DCO).

[gemini-code-assist]

Code Review

This pull request refactors the geometry types in the psm and tap modules to use odb::geom::BoostPolygon90 and odb::geom::BoostPolygon90WithHoles instead of direct boost::polygon aliases. It also optimizes row subtraction in Tapcell::getBoundaryAreas and simplifies Tapcell::getBoundaryEdges. A review comment points out a potential undefined behavior in Tapcell::getBoundaryEdges if the input polygon is empty, suggesting an early return guard.

[gemini-code-assist]

If area is empty, calling area.begin() and dereferencing it with *area.begin() will result in undefined behavior (dereferencing an end iterator). A guard should be added to check if the polygon is empty before accessing its vertices.

  std::vector<Edge> edges;

  if (area.begin() == area.end()) {
    return edges;
  }

  const odb::Point first_pt((*area.begin()).x(), (*area.begin()).y());