feat: use llamaindex everywhere (#525)

* feat: use llamaindex for transcript final title too

* refactor: removed llm backend, replaced with one single class+llamaindex

* refactor: self-review

* fix: typing

* fix: tests

* refactor: extract clean_title and add tests

* test: fix

* test: remove ensure_casing/nltk

* fix: tiny mistake

server/tests/test_utils_text.py

@@ -0,0 +1,21 @@
+import pytest
+
+from reflector.utils.text import clean_title
+
+
+@pytest.mark.parametrize(
+    "input_title,expected",
+    [
+        ("hello world", "Hello World"),
+        ("HELLO WORLD", "Hello World"),
+        ("hello WORLD", "Hello World"),
+        ("the quick brown fox", "The Quick Brown fox"),
+        ("discussion about API design", "Discussion About api Design"),
+        ("Q1 2024 budget review", "Q1 2024 Budget Review"),
+        ("'Title with quotes'", "Title With Quotes"),
+        ("'title with quotes'", "Title With Quotes"),
+        ("MiXeD CaSe WoRdS", "Mixed Case Words"),
+    ],
+)
+def test_clean_title(input_title, expected):
+    assert clean_title(input_title) == expected