tools: visual-review screenshot pipeline

- AGigLineShotActor (dev-only): walks a fixed camera list in -game mode,
  captures via FScreenshotRequest, quits. Test content only.
- ue_build_review_map.py builds /Game/Test/ReviewMap from current content
  (gray floor, key light, sky, MPFB character, 1 m scale cubes).
- render_screenshots.sh: build map -> run game -> collect PNGs into
  gitignored Screenshots/.
- Screenshots/README.md (committed) describes each capture with approval
  state; AGENTS.md gains the visual-review instructions.

MEMORY.md

@@ -71,3 +71,9 @@ Scope: facts and traps that cost time to establish. Planned work lives in [ROADM
 - **Two sessions edit this repo at once.** The other session created the Unreal project and the blank package while this one was documenting. Check `git log` and `git status` before committing, and never `git add -A` blindly: it once swept generated `Game/GigLine/Build/**` logs into a commit. Stages the source files deliberately.
 - **`Build/` under a project is generated**, not source — `FileOpenOrder/*.log` and packaging output. `.gitignore` now covers it alongside `Binaries/`, `Intermediate/`, `Saved/`, `DerivedDataCache/`.
 - **Scope boundary for `0.1.0`:** do not tag `v0.1.0` without an explicit go-ahead from the owner. It is a minor release and carries the walking/driving demo promise; the board's release checks decide when it is ready, not the pace of work.
+
+## 2026-11-07 — Screenshot pipeline
+
+- **`-executePythonScript` + editor is unreliable for captures**: the editor quits right after a *successful* deferred script (async screenshot requests never render), and after `load_map` in a commandlet every `spawn_actor` call returns None — build scenes in the default world instead.
+- **Robust in-game capture recipe**: commandlet builds a map (`ue_build_review_map.py`), then the game runs in `-game` mode and a tiny C++ actor (`AGigLineShotActor`) walks camera setups via `SetViewTarget` + `FScreenshotRequest::RequestScreenshot`. In 5.8 `FScreenshotRequest` has no resolution argument (window size via `-ResX/-ResY`) and no `IsFinished()` — poll `!IsScreenshotRequested()`. Lives in `UnrealClient.h`, not `Misc/ScreenshotManager.h`.
+- **Commandlet-only quirks**: bulk render-target readback (`read_render_target_raw`, `export_render_target`) silently returns empty in commandlets; single-pixel `read_render_target_uv` works. Game targets must use `BuildSettingsVersion.V7`.