cleanup: remove ML artifacts and update gitignore (#1385)

Removed ~86M of untracked ML/video processing artifacts (~/, frames/, mlruns/, output/) and inactive mcp-dashboard-go directory. Updated .gitignore to prevent future accumulation of experiment tracking and output files.

Author: atxtechbro

.gitignore

@@ -86,3 +86,12 @@ mcp/clients/
 # MCP server convenience symlinks (setup-generated executables)
 mcp/servers/*/git_mcp_server.py
 
+# Video processing artifacts
+frames/
+
+# ML experiment tracking
+mlruns/
+
+# General output directory
+output/
+