Add /addword command to add missing Wordle answers

Some real Wordle answers aren't in the bundled answers.txt list. This
adds a REPL command to append a word to answers.txt and remove it from
guesses.txt if present there, since the two lists are meant to be
disjoint.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

wordle_solver/words.py

@@ -10,8 +10,8 @@ from pathlib import Path
 DATA_DIR = Path(__file__).parent / "data"
 
 
-def _load(filename: str) -> list:
-    path = DATA_DIR / filename
+def _load(filename: str, data_dir: Path = DATA_DIR) -> list:
+    path = data_dir / filename
     return [w.strip().lower() for w in path.read_text().splitlines() if w.strip()]
 
 
@@ -25,3 +25,26 @@ def load_extra_guesses() -> list:
 
 def load_all_valid_words() -> list:
     return load_answers() + load_extra_guesses()
+
+
+def add_answer_word(word: str, data_dir: Path = DATA_DIR) -> dict:
+    """Add `word` to the bundled answers list, removing it from the extra
+    guesses list if it's there (the two lists are meant to be disjoint)."""
+    word = word.strip().lower()
+    answers = _load("answers.txt", data_dir)
+    guesses = _load("guesses.txt", data_dir)
+
+    result = {"added": False, "removed_from_guesses": False}
+
+    if word not in answers:
+        answers.append(word)
+        answers.sort()
+        (data_dir / "answers.txt").write_text("\n".join(answers) + "\n")
+        result["added"] = True
+
+    if word in guesses:
+        guesses = [w for w in guesses if w != word]
+        (data_dir / "guesses.txt").write_text("\n".join(guesses) + "\n")
+        result["removed_from_guesses"] = True
+
+    return result