fix: address PR review issues for schematic analysis tools

Eliminate repeated file parsing by extracting _extract_lib_symbols helper
that walks already-parsed sexp_data once instead of re-reading the file
per symbol via PinLocator. Support diagonal wire overlap detection using
cross-product parallelism and 1D projection. Fix wire region inclusion to
use AABB intersection for pass-through wires. Normalize view region
coordinates. Clarify tolerance docstrings across Python, TS, and schema.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

python/kicad_interface.py

@@ -2584,6 +2584,8 @@ class KiCADInterface:
             y1 = float(params.get("y1", 0))
             x2 = float(params.get("x2", 297))
             y2 = float(params.get("y2", 210))
+            x1, x2 = min(x1, x2), max(x1, x2)
+            y1, y2 = min(y1, y2), max(y1, y2)
             out_format = params.get("format", "png")
             width = int(params.get("width", 800))
             height = int(params.get("height", 600))