Remove the 0.5mm query tolerance in favour of exact integer-unit matching
on all coordinate lookups (seed, label bridging, pin matching), mirroring
KiCad's own connectivity algorithm. Callers must supply exact wire endpoint
coordinates (e.g. from list_schematic_wires).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Update tool description and Python docstring to make clear that the
query point must be at a wire endpoint or junction — midpoints of
wire segments are not matched.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Shared-endpoint adjacency already connects all wires meeting at the same
point, making explicit junction handling a no-op duplicate.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Move wire connectivity logic from _handle_get_wire_connections into
commands/wire_connectivity.py. Use KiCad's internal integer unit system
(10,000 IU/mm) with exact coordinate matching instead of tolerance-based
float comparison, mirroring how KiCad itself determines connectivity.
Key improvements:
- Exact integer matching for wire endpoints (O(1) dict lookup vs O(n) grid scan)
- Junction support for T-connections
- Multi-unit symbol support (removed incorrect processed_refs dedup)
- Single public API: get_wire_connections()
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>