fix: resolve all ruff lint errors

- Remove unused imports (sys, re, io, numpy, pytest, BBox, etc.)
- Fix import ordering across all files
- Replace IOError with OSError (Python 3 alias)
- Add noqa for intentional import-check imports
- Move json import to top level in app.py

app.py

@@ -6,17 +6,16 @@ and spacecraft components in space imagery.
 
 from __future__ import annotations
 
+import json
 import logging
 import os
-import sys
 
 import gradio as gr
 from PIL import Image
 
 from src.config import APP_SUBTITLE, APP_TITLE
 from src.inference import LocateAnythingWorker, run_localization
-from src.parsing import ParseResult
-from src.prompts import SPACE_DEBRIS_EXAMPLES, get_example_prompts
+from src.prompts import get_example_prompts
 from src.utils import ensure_rgb, format_json_output, format_metadata, validate_image
 
 logging.basicConfig(level=logging.INFO, format="%(asctime)s %(levelname)s %(message)s")
@@ -59,7 +58,6 @@ def run_inference(
 
         metadata = format_metadata(parsed)
         json_out = format_json_output(parsed)
-        import json
         json_str = json.dumps(json_out, indent=2, ensure_ascii=False)
 
         status = f"Done. Found {parsed.num_detections} object(s)."

src/inference.py

@@ -2,7 +2,6 @@
 
 from __future__ import annotations
 
-import re
 from typing import Any
 
 import torch
@@ -10,8 +9,6 @@ from PIL import Image
 from transformers import AutoModel, AutoProcessor, AutoTokenizer
 
 from src.config import (
-    COORD_MAX,
-    DEFAULT_CONFIDENCE,
     DEVICE,
     DTYPE,
     GENERATION_MODE,
@@ -19,7 +16,7 @@ from src.config import (
     MODEL_ID,
     TEMPERATURE,
 )
-from src.parsing import BBox, ParseResult, parse_boxes
+from src.parsing import ParseResult, parse_boxes
 
 
 class LocateAnythingWorker:
@@ -148,7 +145,7 @@ def run_localization(
     Returns:
         Tuple of (annotated_image, raw_output, parse_result).
     """
-    from src.visualization import draw_boxes, create_no_detection_overlay
+    from src.visualization import create_no_detection_overlay, draw_boxes
 
     if worker is None:
         worker = LocateAnythingWorker()

src/utils.py

@@ -2,7 +2,6 @@
 
 from __future__ import annotations
 
-import io
 import logging
 from typing import Any
 

src/visualization.py

@@ -4,7 +4,6 @@ from __future__ import annotations
 
 from typing import TYPE_CHECKING
 
-import numpy as np
 from PIL import Image, ImageDraw, ImageFont
 
 if TYPE_CHECKING:
@@ -22,10 +21,10 @@ def _get_font(size: int = 14) -> ImageFont.FreeTypeFont | ImageFont.ImageFont:
     """Try to load a reasonable font, fall back to default."""
     try:
         return ImageFont.truetype("arial.ttf", size)
-    except (OSError, IOError):
+    except OSError:
         try:
             return ImageFont.truetype("/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf", size)
-        except (OSError, IOError):
+        except OSError:
             return ImageFont.load_default()
 
 

tests/test_app_smoke.py

@@ -5,14 +5,13 @@ import pytest
 
 def test_app_module_imports():
     """Verify lightweight source modules can be imported without error."""
-    import src.config
-    import src.parsing
-    import src.prompts
-    import src.utils
+    import src.config  # noqa: F401
+    import src.parsing  # noqa: F401
+    import src.prompts  # noqa: F401
 
 
 def test_config_values():
-    from src.config import APP_TITLE, APP_SUBTITLE, MODEL_ID, COORD_MAX
+    from src.config import APP_SUBTITLE, APP_TITLE, COORD_MAX, MODEL_ID
 
     assert MODEL_ID == "nvidia/LocateAnything-3B"
     assert COORD_MAX == 1000
@@ -23,6 +22,7 @@ def test_config_values():
 def test_visualization_import():
     """Verify visualization module imports."""
     import src.visualization
+
     assert hasattr(src.visualization, "draw_boxes")
     assert hasattr(src.visualization, "create_no_detection_overlay")
 
@@ -31,6 +31,7 @@ def test_app_build_callable():
     """Verify the Gradio app builder is importable and callable."""
     try:
         from app import build_app
+
         assert callable(build_app)
     except ImportError:
         pytest.skip("Gradio not available in test environment")
@@ -40,6 +41,7 @@ def test_inference_module_imports():
     """Verify inference module structure without heavy imports."""
     try:
         from src.inference import LocateAnythingWorker
+
         w = LocateAnythingWorker.__new__(LocateAnythingWorker)
         assert not getattr(w, "_loaded", True)
     except ImportError:

tests/test_parsing.py

@@ -1,6 +1,5 @@
 """Tests for the output parsing module."""
 
-import pytest
 from src.parsing import BBox, ParseResult, parse_boxes, parse_points
 
 

tests/test_prompts.py

@@ -1,9 +1,8 @@
 """Tests for prompt templates."""
 
-import pytest
 from src.prompts import (
-    SPACE_DEBRIS_EXAMPLES,
     DETECTION_TEMPLATES,
+    SPACE_DEBRIS_EXAMPLES,
     PromptTemplate,
     build_detect_prompt,
     build_grounding_prompt,

tests/test_visualization.py

@@ -2,8 +2,9 @@
 
 import pytest
 from PIL import Image
+
 from src.parsing import BBox
-from src.visualization import draw_boxes, create_no_detection_overlay, MIN_BOX_SIZE
+from src.visualization import create_no_detection_overlay, draw_boxes
 
 
 @pytest.fixture