fix(scripts): repair broken sys.path setup in utility scripts

clear_cache.py and download_nba_logos.py pointed sys.path at a 'src'
directory relative to the script's own folder (scripts/utils/src and
scripts/src — neither exists), so both crashed on import; they now insert
the project root and import via the src package like the other scripts.
debug_web_manual.py resolved 'project root' to scripts/debug/ instead of
two levels up. fix_nhl_cache.sh is removed: it used Python docstring
syntax in a bash script and invoked clear_nhl_cache.py, which does not
exist anywhere in the repo — it cannot ever have worked in its current
location.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SXb4mKcAkVaxkeTb3YnAdr

scripts/fix_perms/README.md

@@ -31,9 +31,6 @@ owned by the `ledmatrix` service user or by `root`.
   systemd journal access, and the sudoers entries the web interface
   needs to control the display service.
 
-- **`fix_nhl_cache.sh`** — Targeted fix for NHL plugin cache issues
-  (clears the NHL cache and restarts the display service).
-
 - **`safe_plugin_rm.sh`** — Validates that a plugin removal path is
   inside an allowed base directory before deleting it. Used by the web
   interface (via sudo) when a user clicks **Uninstall** on a plugin —