feat: creating FastAPI routes for working with cards

Added 3 routes:
- add_card (add a card via POST request with AddCardBody scheme)
- get_card (get a specific card by card_id)
- get_random_cards (get 10 random cards)

app/base_moderation.py

@@ -0,0 +1,20 @@
+import re
+
+from dirty_words import dirty_words_set
+
+def is_not_empty(text: str) -> bool:
+    """Checks that the text is not empty."""
+    return bool(text.strip())
+
+def has_no_links(text: str) -> bool:
+    """Checks that there are no links in the text."""
+    url_pattern = re.compile(r'https?://\S+|www\.\S+')
+    return not bool(url_pattern.search(text))
+
+def has_no_dirty_words(text: str) -> bool:
+    """Checks that there are no forbidden words in the text."""
+    words = set(re.findall(r'\w+', text.lower()))
+    return not bool(words & dirty_words_set)
+
+def moderate_text(text: str) -> bool:
+    return is_not_empty(text) and has_no_links(text) and has_no_dirty_words(text)