fix(fzk_house): drop ambiguous element counts in Q508 and Q555

Resolves issue #5. Q508 loses the 'Total Architectural Elements: 49'
line (kept structural/levels/spaces/footprint); Q555 loses the
'Existing elements (Bestand): 95' line (kept phase breakdown).
Both counts folded in non-physical entities and were unreproducible.
README v2 checksum updated to match.

README.md

@@ -235,7 +235,7 @@ Verify dataset integrity using SHA-256 checksums:
 ```bash
 # V2 dataset
 shasum -a 256 questions/ifc-bench-v2.csv
-# Expected: 8f08f5d04834a79310eb7de81f2d6812e74d53a01363affdb815bf86dfc4dbf4
+# Expected: cd7034eea0ffd02a09c88f5adc62d9c3981d8e210441aaa340a3a62e6e7fc29f
 
 # V1 dataset (preserved for backwards compatibility)
 shasum -a 256 questions/ifc-bench-v1.csv

questions/ifc-bench-v2.csv

@@ -4007,7 +4007,6 @@ Roof slabs:
    - German attribute names
    - BIM modeling with ARCHICAD authoring",arc,fzk_house,1
 508,"What are the key building metrics including element counts, number of levels, total spaces, and footprint area?","Building Scale:
-   - Total Architectural Elements: 49
    - Total Structural Elements: 46
    - Number of Levels: 2 storeys
    - Total Spaces: 7 defined spaces
@@ -4362,7 +4361,6 @@ All walls have 'Tragende Funktion' property set to 'Nicht definiert' (Not define
    Circulation: 3 elements
      - Bestand: 3",arc,fzk_house,2
 555,"Which elements correspond to renovation work versus existing construction?","Construction Type Analysis:
-   - Existing elements (Bestand): 95
    - Renovation elements: 0
    - New construction: 0
    - Demolition elements: 0