Add tools/webbuild.sh — bake the whole campaign to one wasm

MRPGI (827797a) can now bake a folder of game folders into a single browser
build with its title screen intact, so the entire sixteen-case campaign is one
2.1 MB wasm rather than sixteen separate builds. This wraps that for the repo.
Deploy stays a separate deliberate step.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

README.md

@@ -93,6 +93,19 @@ isn't → Richard Cane → a New Year's ball drop, a pair of lost trousers, and
 barn owl in a 1950s hat who is lit by a different decade than everything around
 him.
 
+## Web build
+
+The whole campaign bakes into a single self-contained wasm — title screen,
+all sixteen cases, ~2.1 MB:
+
+```bash
+./tools/webbuild.sh
+```
+
+Output lands in `MRPGI/web/dist/` (wasm + `index.html` + the macroquad JS
+shim). Preview it with any static server; deploy by copying that directory to
+the host. The shelf's title comes from [cases/collection.json](cases/collection.json).
+
 ## Regenerating art
 
 Sprites are generated locally on MODELBEAST (`flux_local` → `bg_remove_local` →

tools/webbuild.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+# Bake the whole campaign into one wasm and stage it in MRPGI/web/dist/.
+# The engine boots into its title screen with all cases on the shelf.
+#
+#   ./tools/webbuild.sh
+#
+# Deploy is a separate, deliberate step — see README "Web build".
+set -e
+ENGINE="${MRPGI:-$HOME/Documents/MRPGI}"
+cd "$(dirname "$0")/.."
+"$ENGINE/web/build.sh" "$(pwd)/cases"
+echo "preview locally:  cd $ENGINE/web/dist && python3 -m http.server 8899"