ci/github-script: move from ci/labels

This just moves things around to use less specific naming - `labels` is
only *one* script that can potentially be run locally while still being
written in github-script. Later, we can add more.

ci/github-script/run.js

@@ -0,0 +1,45 @@
+#!/usr/bin/env node
+import { execSync } from 'node:child_process'
+import { mkdtempSync, rmSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { getOctokit } from '@actions/github'
+import labels from './labels.cjs'
+
+if (process.argv.length !== 4)
+  throw new Error('Call this with exactly three arguments: ./run OWNER REPO')
+const [, , owner, repo] = process.argv
+
+const token = execSync('gh auth token', { encoding: 'utf-8' }).trim()
+
+const tmp = mkdtempSync(join(tmpdir(), 'labels-'))
+try {
+  process.env.GITHUB_WORKSPACE = tmp
+  process.chdir(tmp)
+
+  await labels({
+    github: getOctokit(token),
+    context: {
+      payload: {},
+      repo: {
+        owner,
+        repo,
+      },
+    },
+    core: {
+      getInput() {
+        return token
+      },
+      error: console.error,
+      info: console.log,
+      notice: console.log,
+      setFailed(msg) {
+        console.error(msg)
+        process.exitCode = 1
+      },
+    },
+    dry: true,
+  })
+} finally {
+  rmSync(tmp, { recursive: true })
+}