chore: delete Agno dead code (Phase 1)

Closes #307

Agno was imported by nothing, had undefined-variable bugs,
and was not a declared dependency.

Removed:
- agentic_security/agents/ (operator_agno.py)
- docs/mcp_agno_integration.md
- .gitignore reference to operator_agno.py

No agno references remain in source code.
Pre-existing test failures (missing tabulate module) confirmed
unrelated to this change via git stash verification.

Author: jasoncobra3

.gitignore

@@ -19,9 +19,11 @@ docx/
 agentic_security.toml
 /venv
 *.csv
-agentic_security/agents/operator_agno.py
+
 .claude/
 plan.md
 auto_loop.sh
 agentic_security/static/elm-stuff/
 agentic_security/static/node_modules/
+.cache/
+COMMIT_MSG.txt