fix: resolve all ruff lint errors across V6+ GUIs, v7 module, and FPGA cosim scripts

Fixes 25 remaining manual lint errors after auto-fix pass (94 auto-fixed earlier):
- GUI_V6.py: noqa on availability imports, bare except, unused vars, F811 redefs
- GUI_V6_Demo.py: unused app variable
- v7/models.py: noqa F401 on 8 try/except availability-check imports
- FPGA cosim: unused header/status/span vars, ambiguous 'l' renamed to 'line',
  E701 while-on-one-line split, F841 padding vars annotated

Also adds v7/ module, GUI_PyQt_Map.py, and GUI_V7_PyQt.py to version control.
Expands CI lint job to cover all 21 maintained Python files (was 4).

All 58 Python tests pass. Zero ruff errors on all target files.

9_Firmware/9_3_GUI/GUI_V6_Demo.py

@@ -8,8 +8,6 @@ All buttons work, simulated radar data is generated in real-time
 
 import tkinter as tk
 from tkinter import ttk, messagebox
-import threading
-import queue
 import time
 import numpy as np
 import matplotlib.pyplot as plt
@@ -17,10 +15,9 @@ from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
 from matplotlib.figure import Figure
 import logging
 from dataclasses import dataclass
-from typing import List, Dict, Optional
+from typing import List, Dict
 import random
 import json
-import os
 from datetime import datetime
 
 # Configure logging
@@ -1200,7 +1197,7 @@ def main():
         root = tk.Tk()
         
         # Create application
-        app = RadarDemoGUI(root)
+        _app = RadarDemoGUI(root)  # noqa: F841 — keeps reference alive
         
         # Center window
         root.update_idletasks()