RE-15-09: Decode real door dimensions + emit IfcOpeningElement / IfcRelVoidsElement / IfcRelFillsElement

[DrunkOnJava]

Problem

v0.2.0 emits 112 IFCDOOR entities at correct placement but
without:

• Real width/height/sill dimensions (currently placeholder).
• Host wall void (IfcOpeningElement).
• IfcRelVoidsElement (door voids host wall).
• IfcRelFillsElement (door fills the opening).

Without these the wall has no hole and BlenderBIM shows doors
as floating panels.

Scope

• Decode FamilyInstance dimensions for doors (width, height,
  sill height, hand/facing flags).
• For each door: emit IfcOpeningElement at the host-wall
  location with real width/height.
• Emit IfcRelVoidsElement(host_wall, opening) +
  IfcRelFillsElement(opening, door).

Acceptance criteria

• All 112 doors in 2024_Core_Interior.rvt have associated
  IfcOpeningElement + Void + Fill triples.
• Host walls show holes in BlenderBIM where doors are.
• Test fixture asserts opening counts match door counts.

Related

• Umbrella: M4-04: Recover doors and windows with host relationships #32 (M4-04 Recover doors and windows with host
  relationships)
• Per ROADMAP CLASS-06