craft-proof it — the dialogue-dash exception applies after ? and ! only, so Finì. —domani partiamo. gets its capital mark again (#496 review)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/proof/src/it/grammar.rs

@@ -167,8 +167,8 @@ fn ends_sentence(gap: &str, prev: &str) -> bool {
     let rest = after_marks.trim_start_matches(CLOSING);
     // (Not the object placeholder `\u{1}`: `Chi era?\u{1} era Marco.` still starts a sentence.)
     // `«Vai?» disse lui.` and `—Vai? —disse lui.`: the narration after a quoted question or
-    // exclamation, or after a dialogue dash, goes on in lower case.
-    if rest.contains('—') || (end != '.' && after_marks.starts_with(|c| c != '\u{1}' && CLOSING.contains(&c))) {
+    // exclamation (not after a period: `Finì. —domani` starts a sentence), or after a dialogue dash, goes on in lower case.
+    if end != '.' && (rest.contains('—') || after_marks.starts_with(|c| c != '\u{1}' && CLOSING.contains(&c))) {
         return false;
     }
     rest.starts_with(char::is_whitespace) && rest.trim_start().chars().all(|c| matches!(c, '"' | '“' | '«' | '(' | '[' | '\'' | '—'))
@@ -417,6 +417,8 @@ mod tests {
             assert!(fixes(t).is_empty(), "{t}: {:?}", fixes(t));
         }
         assert!(fixes("Vado a Roma? sì.").contains(&pair("sì", "Sì")), "a bare question still ends the sentence");
+        // After a period the dash opens the next line of speech: a sentence starts.
+        assert!(fixes("Finì. —domani partiamo.").contains(&pair("domani", "Domani")), "{:?}", fixes("Finì. —domani partiamo."));
         // An inline object (`\u{1}`) is not a closing quote.
         assert!(fixes("Chi era?\u{1} era Marco.").contains(&pair("era", "Era")), "{:?}", fixes("Chi era?\u{1} era Marco."));
     }