AutoDrill v1.6

Mindustry v158.1 — Placement validation overhaul, Erekir fixes, orphan bridge elimination.

Merged PRs

PR #37 — @derekShaheen — Unified placement validation pipeline (canPlaceBlock, canPlaceWithoutPlanCollision, commitPlans). Dry-run commit pattern for all drill types. Full-footprint placement check for multi-tile blocks. Orphan bridge elimination (bridges only placed if connected to a partner). Fixed OptimizationDrill settings key mapping (mechanicalDrill was reading "laser-drill-max-tiles"). Debug logging support.
PR #27 — @Arasal — Fixed wall drill settings key returning 0. Fixed Erekir Plasma Bore direction offsets for LEFT/DOWN. Split drill/duct offset calculations.
PR #36 — @WeslieDE — Compatibility update to Mindustry v157.4.