Initial commit: Conflict Checker

Cross-discipline design-contradiction checker for construction drawing
sets. Standalone tool broken out from Iron_Bid; a pipeline stage may
later fold back into Iron_Bid.

Pipeline: PDF->images -> per-sheet assertion extraction -> deterministic
clustering by location -> per-cluster reasoning -> report.
Includes CLI (cli/run_check.py) and web UI (backend/main.py).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/.llm_cache/79dc2be35041085078ca2fea9a8f180d6f07b3beff6b0029dd6136d38416beba.json

@@ -0,0 +1 @@
+{"conflicts": [{"conflict_id": "A2501_01", "category": "tag_or_reference_inconsistency", "severity": "medium", "confidence": "high", "location": "Sheet A25.01, New RTU locations and detail area", "disciplines": ["Architectural"], "sheets": ["A25.01"], "description": "Keynote 2 on the roof plan calls for new mechanical roof curbs, and a 'ROOF CURB DETAIL' is provided on the same sheet. However, the detail is not numbered and is not referenced in the keynote or by the plan callouts, leaving it unclear if this is the correct detail to be used for the new RTUs. This creates ambiguity for the contractor on which standard to follow.", "evidence": [{"discipline": "Architectural", "sheet": "A25.01", "source_text": "KEYNOTES\n2. NEW RTU, PROVIDE NEW MECHANICAL ROOF CURBS AS NECESSARY TO ACCOMODATE NEW RTU. GC TO INSTALL FLASHING PER PER ROOFING MANUFACTURING STANDARDS. GC SHALL COORDINATE ROOF WORK WITH LL REQUIREMENTS TO MAINTAIN EXISTING ROOFING WARRANTY. REFER TO MEP DRAWINGS FOR MORE INFORMATION.", "asserted_value": "Requirement for new roof curbs with no reference to a specific detail."}, {"discipline": "Architectural", "sheet": "A25.01", "source_text": "ROOF CURB DETAIL", "asserted_value": "An un-numbered and un-referenced detail for a roof curb is provided."}], "recommended_resolution": "coordinate drawings"}]}