fix(cli): restore a publishable manifest and a real bin entry point

The compiler shim has been unpublishable and uninstallable-as-a-CLI. Two gaps,
both fixed here.

1. NO MANIFEST. `packages/affinescript-cli/` ships mod.js, pins.js, mod_test.js
   and mod.d.affine but has no package.json, jsr.json or deno.json - and git
   history shows one was never committed. The shim is live on JSR as
   @hyperpolymath/affinescript 0.1.2, so it was published from an untracked
   manifest and cannot be republished from a clean checkout. pins.js even
   instructs the maintainer to "bump THIS package's deno.json version in
   lockstep" with a file that is not in the tree.

2. NO `bin`. NOTHING in this repository declares a `bin` field, so nothing
   installs as an `affinescript` command. mod.js self-executes when it is the
   entry module but carries no hashbang, so it cannot be a `bin` target on
   Unix. bin/affinescript.js adds the hashbang and delegates to mod.js's
   exported run(); no behaviour moves.

VERIFIED, not assumed: `bun bin/affinescript.js --version` and
`node bin/affinescript.js --version` both resolve the pinned binary, verify its
checksum, exec it, and print a version.

package.json (not deno.json) because Deno is being removed estate-wide per the
2026-08-26 owner ruling; the manifest is npm-compatible so Bun, npm and Node all
consume it. Version 0.1.2 matches what is already on JSR - same code, same
version, two registries.

FOUND WHILE TESTING, not fixed here: the shim resolves the v0.1.1 release
binary, but that binary self-reports 0.1.0, while dune-project and lib/version.ml
say 0.1.1. The v0.1.1 release was cut before the version bump landed. Flagged
rather than silently re-pinned.

STILL OPEN, needs a new tag: v0.2.0 has ZERO release assets. Root cause is in the
logs - "HTTP 422: Cannot upload assets to an immutable release": the release was
published before the build legs uploaded. release.yml has ALREADY been fixed for
this (create as draft, upload, publish last, sealing atomically) but that fix has
never been exercised. v0.2.0 is immutable and cannot be repaired retroactively;
it needs a fresh tag to run the corrected workflow.

Author: hyperpolymath

packages/affinescript-cli/bin/affinescript.js

@@ -0,0 +1,16 @@
+#!/usr/bin/env bun
+// SPDX-License-Identifier: MPL-2.0
+// Copyright (c) 2026 Jonathan D.A. Jewell (hyperpolymath) <j.d.a.jewell@open.ac.uk>
+//
+// Executable entry point for the `affinescript` command.
+//
+// WHY THIS FILE EXISTS. `mod.js` already self-executes when it is the entry
+// module, but it carries no hashbang, so it cannot be the target of a
+// package.json `bin` field on Unix. This wrapper adds the hashbang and nothing
+// else — all behaviour stays in mod.js.
+import { run } from "../mod.js";
+
+const argv = typeof Deno !== "undefined" ? Deno.args : process.argv.slice(2);
+const code = await run(argv);
+if (typeof Deno !== "undefined") Deno.exit(code);
+else process.exit(code);

packages/affinescript-cli/package.json

@@ -0,0 +1,30 @@
+{
+  "name": "@hyperpolymath/affinescript",
+  "version": "0.1.2",
+  "description": "Ergonomic front door for the AffineScript compiler: downloads the pinned native binary for the host platform, verifies its SHA-256, caches it, and execs it.",
+  "license": "MPL-2.0",
+  "type": "module",
+  "bin": {
+    "affinescript": "./bin/affinescript.js"
+  },
+  "exports": {
+    ".": "./mod.js"
+  },
+  "files": [
+    "bin/affinescript.js",
+    "mod.js",
+    "pins.js",
+    "mod.d.affine"
+  ],
+  "engines": {
+    "bun": ">=1.0.0",
+    "node": ">=18.0.0"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/hyperpolymath/affinescript.git",
+    "directory": "packages/affinescript-cli"
+  },
+  "homepage": "https://github.com/hyperpolymath/affinescript",
+  "keywords": ["affinescript", "compiler", "affine-types", "wasm"]
+}