feat(a2b): first-pass texture render — full-screen event-CG layer

Wire asset resolution into a live Godot render. VM executes set-texture ->
ResourceMap resolves (scene,resId) -> files[section_base+resId] across all
archives -> pre-converted BMP -> composite behind the dialogue. The full-screen
event-CG layer (EV052*) renders end-to-end from the executed bytecode.

- Age.Engine/Sys4/ResourceMap.cs: Resolve + BMP TexturePath; Paths: asset JSONs
- GodotAdvHost: create/set/draw-texture -> TextureRect in a _stage layer
- IHost.DrawTexture + VM dispatch extended with dst x/y (draw-texture args 7/8)
- project.godot 800x600; convert_agf.py all-archive + --scene batch
- engine 8/8, C# --selftest still byte-matches vm0 trace (VM behaviour unchanged)

Known limitations (next chunk = graphics geometry/blend subsystem):
- sprites + BG* via the CG-load subroutine get garbage dst/size — native ops
  stubbed (0x208 get-texture-size + sprite position/anim chain)
- AE* fades draw opaque/instant (no alpha); no chromakey
- slot model approximates the game's immediate-mode blit-onto-slot-0 canvas
- AGF pre-converted to BMP offline (runtime decoder deferred)
See docs/phase-a-slice-plan.md (A2b section).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/tools-reference.md

@@ -66,7 +66,7 @@ All opcode knowledge (ABI, semantics, provenance, `depends_on`) is hand-edited *
 | `parse_sys4ini.py` | Parse `SYS4INI.BIN` (S4IC422, LZSS-compressed) into the authoritative asset index — name ↔ archive ↔ offset ↔ size for all DATA*.ALF (the `resId→file` answer key). | `parse_sys4ini.py [--check]` (`--check` validates vs `extracted/` + `.ALF` sizes) | `姫狩り…/SYS4INI.BIN` → `build/asset-index.json` |
 | `resolve_asset.py` | ★ **The static asset resolver.** SYS4INI is sectioned (one per scene: `SCxxxx.BIN` + its cross-archive manifest; `file_number` = index within section). Resolves `resId → files[section_base(scene) + resId]` for graphics AND audio, no capture. | `resolve_asset.py --build` · `resolve_asset.py <SCENE> [resId]` | `build/asset-index.json` → `build/asset-sections.json`; resolves any (scene, resId) |
 | `resolve_frida_reads.py` | Rescue noisy Frida archive-read offsets → asset names via the index (per-archive range search; drops 0x20000 paging reads); recovers the per-scene asset load order. | `resolve_frida_reads.py [reads.log] [-o out.json]` | `build/frida-reads.log` + `build/asset-index.json` → `build/frida-asset-loads.json` |
-| `convert_agf.py` | Convert named AGF stills to BMP via `AGF2BMP2AGF.exe`. | `convert_agf.py EV001AA.AGF …` | `extracted/DATA2|DATA5/*.AGF` → `build/textures/*.BMP` |
+| `convert_agf.py` | Convert AGF stills to BMP via `AGF2BMP2AGF.exe` (searches all `extracted/DATA*`). `--scene` batch-converts a scene's whole SYS4INI manifest — feeds the Godot render. | `convert_agf.py EV052CA.AGF …` · `convert_agf.py --scene SC0000` | `extracted/DATA*/*.AGF` → `build/textures/*.BMP` |
 
 ## Runtime capture (Frida)