fix(i18n): persist uncommitted translation snapshots

scripts/translation-pairing-git.ts

@@ -0,0 +1,37 @@
+/** Git-blob operations owned by the bilingual pairing workflow. */
+
+import { spawnSync } from 'node:child_process'
+import { createHash } from 'node:crypto'
+
+/** Full SHA-1 Git blob hash (the 40-hex format used by pairing records). */
+export function gitBlobHash(content: Buffer): string {
+  const hash = createHash('sha1')
+  hash.update(`blob ${content.byteLength}\0`)
+  hash.update(content)
+  return hash.digest('hex')
+}
+
+/**
+ * Persist exact working-tree bytes so a pairing record can later recover them
+ * with `git cat-file`, even when they have never appeared in the index or a
+ * commit. The returned object ID is checked against the pairing format's own
+ * content hash before the caller writes a sidecar.
+ */
+export function storeGitBlob(root: string, content: Buffer): string {
+  const expected = gitBlobHash(content)
+  const result = spawnSync('git', ['-C', root, 'hash-object', '-w', '--stdin'], {
+    input: content,
+    maxBuffer: 1 << 26,
+  })
+  if (result.error) {
+    throw new Error(`git hash-object -w --stdin failed: ${result.error.message}`, { cause: result.error })
+  }
+  if (result.status !== 0) {
+    throw new Error(`git hash-object -w --stdin failed with status ${String(result.status)}: ${result.stderr.toString('utf8').trim()}`)
+  }
+  const stored = result.stdout.toString('utf8').trim()
+  if (stored !== expected) {
+    throw new Error(`git hash-object -w --stdin returned unexpected object ID ${JSON.stringify(stored)}; expected ${expected}`)
+  }
+  return stored
+}