Add Ruff linter in CI

.drone.yml

@@ -0,0 +1,13 @@
+kind: pipeline
+name: default
+type: docker
+
+on:
+  push:
+
+steps:
+  - name: lint
+    image: python:3.12
+    commands:
+      - pip install --root-user-action=ignore -r requirements.txt
+      - ruff check .

frontend/main.py

@@ -2,7 +2,6 @@ import pandas as pd
 import streamlit as st
 import matplotlib.pyplot as plt
 import seaborn as sns
-from pandas.api.types import is_numeric_dtype
 
 st.set_page_config(
     page_title="Project Miner",

requirements.txt

@@ -0,0 +1,5 @@
+matplotlib>=3.5.0
+pandas>=1.5.0
+seaborn>=0.12.0
+streamlit>=1.35.0
+ruff>=0.4.8