fix(i18n): count a word per character where a script has no separators

untranslated() asks what share of a translation's words are Latin. WORDS matched runs of letters, and Han, Kana, Thai, Lao, Khmer and Myanmar write without separators, so a whole sentence came back as one token. Two Latin product names inside it carried that token's latin_share past a half, which made the ratio 1.0 and condemned a sound translation.

Measured on a Japanese rendering of "Runs Playwright in Docker with stable browser settings": one token, latin_share 0.516, ratio 1.00 against a threshold of 0.9. The six-word floor removed in 27d59f4bd4 had hidden this, because a separator-less script never reaches six words; dropping it as vacuous missed that it was the only guard those scripts had.

WORDS now takes one character of such a script as one word, with the single-character branch first so the run branch cannot swallow the sentence again. Ten real entries against both patterns: the old one errs on two, the new one on none, and every true positive survives, including Cyrillic welds like CI Деbugging and an English answer in a Japanese catalog.

The ranges are codepoints because a formatter rewrites an escape into the character it names, and the resulting literal blob cannot be reviewed.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

tests/unit/python/utils/i18n/test_damage.py

@@ -67,6 +67,34 @@ class TestWrongScript(unittest.TestCase):
     def test_a_translation_without_a_word_is_kept(self) -> None:
         self.assertEqual(reason("Status", "100 %", "be"), "")
 
+    def test_a_separatorless_script_counts_one_word_per_character(self) -> None:
+        """Japanese and Chinese write without spaces, so a run-based pattern
+        returns the whole sentence as one token, and two Latin product names
+        inside it carry that token past a half and the ratio to 1.0."""
+        self.assertEqual(
+            reason(
+                "Runs Playwright in Docker with stable browser settings",
+                "安定したブラウザ設定でDockerでPlaywrightを実行",
+                "ja",
+            ),
+            "",
+        )
+        self.assertEqual(
+            reason("Run Playwright in Docker", "在Docker中运行Playwright", "zh"), ""
+        )
+
+    def test_a_separatorless_script_answered_in_english_is_still_condemned(
+        self,
+    ) -> None:
+        self.assertEqual(
+            reason(
+                "Runs Playwright in Docker with stable settings",
+                "Runs Playwright in Docker with stable browser settings",
+                "ja",
+            ),
+            "untranslated",
+        )
+
 
 class TestForeignScript(unittest.TestCase):
     """A Latin-script language came back in a script it does not use.