Refactor error logging and session addition in lua-plugins

This commit improves the clarity and conciseness of error logging in monitoring.lua by renaming 'failure' to 'error'. Extracted add_session invocation out of conditions to reduce redundancy. Additionally, some unnecessary server port variables were removed to tighten the code. Minor formatting fixes were also made in telegram.lua and geoip.lua.

Signed-off-by: Christian Roessner c@roessner.co