Promote Wild Gunman (U) from _wip to top-level project

Moves Wild Gunman (U) from _wip/ to Wild Gunman (U)/ with full ROM build:
- Adds header.s, chr.s, linker.cfg (HEADER+PRG+CHR segments)
- Updates Makefile to build and verify reconstructed.nes vs rom.nes
- Adds rom.nes copy + copilot/rom.nes symlink per repo convention
- Verified byte-identical build

Pass 1 complete: full code/data classification (~20% code / ~80% data)
Pass 2 partial: routine headers for all labels, semantic naming for key
routines (Reset, NmiHandler, MainStateDispatch, MainLoopBody, etc.),
zero-page aliases in locals.inc

Updates root OVERVIEW.md:
- Removes Wild Gunman from _wip skeleton table (23 -> 22 skeletons)
- Adds Wild Gunman as #13 in numbered inventory (BYTE-IDENTICAL, Pass 2)
- Updates summary count from 12 to 13 projects

Wild Gunman (U)/copilot/locals.inc

@@ -0,0 +1,18 @@
+; Wild Gunman (U) zero-page aliases - Pass 2
+; Semantic names for addresses with observed usage patterns; ZpXX names for
+; addresses whose role is not yet uniquely determined.
+
+GameMode           = $30 ; Current game mode/state, set to 1 during reset.
+NmiPhase           = $20 ; NMI phase flag, set to 1 by NMI handler.
+NmiFlag            = $22 ; NMI flag, set to 1 by NMI handler.
+Timer2F            = $2F ; Timer incremented each frame in main loop.
+Ctrl1              = $16 ; Controller 1 state, checked in MainStateDispatch.
+Mode38             = $38 ; Mode byte checked in MainStateDispatch.
+OAMBase            = $05EC ; OAM/sprite base address used in reset init.
+SpriteData         = $05F0 ; Sprite data destination in reset init.
+
+; Generic zero-page aliases (role not yet uniquely determined)
+Zp00               = $00 ; Used as indirect pointer lo in RAM clear loop
+Zp01               = $01 ; Used as indirect pointer hi in RAM clear loop
+Zp08               = $08 ; Set to $90 during reset (PPUCTRL value)
+Zp09               = $09 ; Set to $02 during reset