fix(web): integrate compiled game WASM into the web build (#72)

[proggeramlug]

Fixes #72.

Problem

./native/web/build.sh game.ts never produced a working game:

• build.sh compiled the game to a throwaway /tmp/bloom_game.html and copied an unrelated template, so the game WASM was never loaded — bloom_glue.js only console.warn'd.
• The FFI bridge was double-converting: it manually NaN-box-converted every argument, but Perry's runtime already wraps the ffi namespace (wrapFfiForI64), delivering plain JS values and re-encoding returns. The manual conversion would have crashed.
• Latent build.sh bug: it cd'd into the web crate, then tested the relative game path from the wrong cwd, silently skipping compilation.

Approach

Reimplementing Perry's ~280-function rt runtime in JS (the issue's suggested approach #1) is infeasible. Instead, reuse Perry's self-contained HTML as the carrier of its own correct runtime + NaN-boxing, and splice the Bloom engine into it.

Changes

• bloom_glue.js — rewritten as the engine bootstrap + FFI bridge following Perry's plain-value contract. Maps bloom_* straight through, routes string/asset params to the _str/_bytes variants, wires input/audio/HiDPI canvas, and drives the rAF game loop via Perry's global callWasmClosure (runGame short-circuits to bloom_run_game on web, platform === 7).
• splice_game.py (new) — injects the Bloom canvas + a synchronously-created window.__bloomReady promise + the deferred bootstrap module into Perry's HTML, and gates the game's bootPerryWasm() call on that promise so the game boots only after the engine + FFI are live. Anchored to the boot block so it ignores decoy .catch( in the runtime.
• index.html — now a thin engine-only page (no-game case).
• build.sh — resolves the game path up-front (bug fix), compiles to a temp dir, splices into dist/web/index.html, cleans up.
• CLAUDE.md — updated file roles + the FFI value contract.

Validation

Verified end-to-end against the real Perry compiler (v0.5.1206) and a full wasm-pack engine build of examples/pong: the pipeline produces dist/web/index.html containing Perry's runtime, the embedded game WASM, the gated boot, and the Bloom canvas; every pkg export the bridge references exists; the splicer correctly ignores decoy patterns; temp files are cleaned up; all new JS/Python passes syntax checks.

Browser-runtime behavior (WebGPU surface creation, live closure dispatch) was not exercised headless — cd dist/web && python3 -m http.server 8080 would confirm the last mile. Note the build needs PERRY_ALLOW_PERRY_FEATURES=1 (or bloom/* in the host perry.allow.nativeLibrary) since Bloom links native libraries.