ci: harden Tier CI result handling and dashboard polish (#3373)

This PR is a follow-up improvement to the CVA6 Tier CI flow introduced in PR #3285. It focuses on hardening Tier CI result handling and polishing a few dashboard presentation details.

Co-authored-by: JeanRochCoulon <jean-roch.coulon@thalesgroup.com>

Author: AlexChenIC

.github/scripts/dashboard_tiers/generate_dashboard.py

@@ -10,6 +10,7 @@
 import argparse
 import json
 import os
+import shutil
 from datetime import datetime, timezone
 from pathlib import Path
 
@@ -310,6 +311,14 @@ def main():
     with open(output_file, "w") as f:
         f.write(html)
 
+    # Copy static dashboard assets, such as the local OpenHW logo.
+    static_dir = Path(__file__).parent / "static"
+    if static_dir.exists():
+        assets_dir = output_dir / "assets"
+        if assets_dir.exists():
+            shutil.rmtree(assets_dir)
+        shutil.copytree(static_dir, assets_dir)
+
     print(f"Dashboard generated: {output_file}")
     print(f"  Workflows: {len(workflows)}")
     for wf in workflows: