Promote Xevious (U) and Zanac (U) from _wip/ to NROM/

- Xevious (U): Promoted from _wip/NROM/Xevious (U)/ to NROM/Xevious (U)/ - Pass 3 complete: 34.5% code coverage, 143 semantic entry points, 4 named data tables, ~20 semantic ZP aliases - NROM mapper 0, 32 KB PRG, 8 KB CHR, horizontal mirroring - Zanac (U): Promoted from _wip/UNROM/Zanac (U)/ to NROM/Zanac (U)/ - Pass 3 complete: 34.5% code coverage (bank 7 only), 133 semantic entry points, 26 named data tables, 14 semantic ZP aliases - UNROM mapper 2, 128 KB PRG (8 banks), no CHR - Bank 7 fixed at CPU -; banks 0-6 switchable at 000- - Bank 7 assembled separately as prg.07.s with .org Both projects build byte-identical. Updated root README.md inventory, per-project details, and WIP.md accordingly. Move Zanac (U) to UNROM/ mapper directory Zanac (U) is a UNROM (mapper 2) game, not NROM (mapper 0). Move it to the correct mapper directory and update README.md and WIP.md references accordingly. Update project counts in WIP.md (857->856 total, UNROM 98->97 projects). Promote Mermaids of Atlantis (U) from _wip/ to MAPPER8/ Additional cleanup of Mermaids of Atlantis
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+# Zanac (U)
+
+## Status
+
+**Pass 3 complete.** All address-derived `Label_XXXX` names have been replaced
+with semantic entry-point names (133 routines) plus address-based names for
+remaining branch targets (~212 `Sub_XXXX`/`Next_XXXX`/`Skip_XXXX`/`Exit_XXXX`).
+All raw `$XXXX` jsr/jmp operands replaced with label references. Zero-page
+aliases renamed to semantic names (14 named). Data tables named (26 tables).
+The project builds and verifies byte-identical to the original ROM.
+
+`make` assembles `header.s`, `prg.s`, `prg.07.s`, links them with `ld65` and compares the
+result against `rom.nes`:
+
+```
+Byte-identical ROM verified.
+```
+
+### Pass 1 results
+
+| Metric | Value |
+|--------|-------|
+| PRG size | 131072 bytes (128 KB) at file offset $0010 |
+| Code | 6206 bytes (37.9% of bank 7) |
+| Instructions | 2977 |
+| Bank 7 routines | 391 labels traced |
+| Banks as data | Banks 0-6 (switchable $8000-$BFFF) |
+
+### Pass 2 results
+
+| Metric | Value |
+|--------|-------|
+| Semantic entry-point names | 133 (Reset, NmiHandler, InputRead, ObjInitCall, ObjMoveCall, ObjDrawCall, ObjUpdateCall, SetOamPtrs, WaitVblank, GameModeDispatch, etc.) |
+| Internal branch labels | ~212 (`Sub_XXXX`/`Next_XXXX`/`Skip_XXXX`/`Exit_XXXX`) |
+| Raw `$XXXX` jsr/jmp operands | 0 (all replaced with label references) |
+| Raw `$XXXX` branch operands | 0 (all replaced with label references) |
+| Remaining `Label_XXXX` | 0 (all replaced) |
+
+### Pass 3 results
+
+| Metric | Value |
+|--------|-------|
+| Semantic zero-page aliases | 14 (Reset, NmiHandler, InputRead, ObjInitCall, ObjMoveCall, ObjDrawCall, ObjUpdateCall, SetOamPtrs, WaitVblank, GameModeDispatch, etc.) |
+| Named data tables | 26 (JumpTable, IndexTable, SpriteTable, TextTable, etc.) |
+| Raw `$XXXX` jsr/jmp operands | 0 |
+| Raw `$XXXX` branch operands | 0 |
+| Remaining `Label_XXXX` | 0 |
+
+### Pass 1 notes
+
+- Bank 7 (last 16 KB, fixed at CPU $C000-$FFFF) was traced from vectors:
+  NMI=$CE8D, RESET=$E7BF, IRQ=$CEC4. Bank 7 code is assembled separately
+  as `prg.07.s` with `.org $C000` and linked at file offset $1C010.
+- Banks 0-6 (switchable at $8000-$BFFF) are emitted as raw `.byte` data;
+  bank-switch analysis is needed to trace code in those banks
+- Seven invalid opcode addresses found: $D506, $D876, $E15B, $E44B, $E520,
+  $E909, $F0FE (likely data mis-decoded as opcodes or vice versa)
+
+## ROM
+
+| Property | Value |
+|----------|-------|
+| Format | iNES |
+| Mapper | 2 |
+| Board | UNROM |
+| Mirroring | Horizontal |
+| Four-screen VRAM | no |
+| Battery | no |
+| PRG | 128 KB (8 x 16 KB), at file offset $0010 |
+| CHR | none |
+| Trainer | none |
+| Footer | none |
+| NMI vector | $CE8D |
+| RESET vector | $E7BF |
+| IRQ vector | $CEC4 |
+| ROM file | `Zanac (U).nes` |
+| SHA-256 | `7e75a19b9e11715c0eb19a2017a322df02f5cf4f7b30acef0fa7a0615236bda4` |
+
+### Header notes
+
+- none
+
+## Open work
+
+- **Pass 1** - complete. Bank 7 traced (37.9% code); banks 0-6 as raw data.
+  Build verifies byte-identical.
+- **Pass 2** - complete. All 133 entry points have semantic names;
+  ~212 internal branch labels remain as address-based names;
+  All raw `$XXXX` jsr/jmp/branch operands replaced with label references.
+- **Pass 3** - complete. Semantic zero-page aliases applied (14 named).
+  26 data tables named (JumpTable, IndexTable, SpriteTable, TextTable, etc.).
+- **Promotion** to `NROM/<name>/` once ready, as `git mv`.
+
+## Files
+
+| File | Purpose |
+|------|---------|
+| `prg.s` | Pass 3 disassembly (banks 0-6 as raw `.byte` data) |
+| `prg.07.s` | Pass 3 disassembly for bank 7 (fixed at CPU $C000-$FFFF) |
+| `header.s` | iNES header include |
+| `prg.bin` | 131072 bytes (128 KB) PRG image |
+| `rom.nes` | byte-identical copy of the original ROM |
+| `linker.cfg` | HEADER / PRG / PRG7 memory areas |
+| `prg.07.cfg` | Linker config for assembling prg.07.bin |
+| `symbols.inc` | NES hardware register names |
+| `locals.inc` | zero-page aliases (14 semantic names applied) |
+| `Makefile` | build and byte-identity check |