[Request] Add a convar to turn on/off plugin.

[HotoCocoaco]

Although sm plugins load/unload works, a better & safer way of achiving this that doesn't crash could be handy.
Crash: https://crash.limetech.org/wjtwpn5hqdvq/console

last console output before crash:

7178	42899.145841	L 05/11/2024 - 18:40:11: [Custom Votes] Last vote ( change map to szf ) passed. Map was changed from scp_city_v2 to szf_atlantic_a4.
7179	42899.160935	[SM] The loading lock is no longer in effect.
7180	42899.161694	L 05/11/2024 - 18:40:11: server_cvar: "mp_disable_respawn_times" "0.000000"
7181	42899.162392	L 05/11/2024 - 18:40:11: server_cvar: "mp_friendlyfire" "0.000000"
7182	42899.162910	L 05/11/2024 - 18:40:11: server_cvar: "mp_scrambleteams_auto" "1.000000"
7183	42899.163466	L 05/11/2024 - 18:40:11: server_cvar: "tf_spawn_glows_duration" "10.000000"
7184	42899.171683	L 05/11/2024 - 18:40:11: World triggered "Round_Stalemate"
7185	42899.171708	L 05/11/2024 - 18:40:11: Team "Red" current score "0" with "0" players
7186	42899.171736	L 05/11/2024 - 18:40:11: Team "Blue" current score "0" with "1" players
7187	42899.213869	[SM] Plugin SCP: Secret Fortress unloaded successfully.
7188	42899.213967	[SM] Loading is now locked; no plugins will be loaded or re-loaded.
7189	42899.214229	L 05/11/2024 - 18:40:11: server_cvar: "mp_timelimit" "40"
7190	42899.215936	[SM] Changing map to szf_atlantic_a4...
7191	42899.216019	L 05/11/2024 - 18:40:11: [basecommands.smx] "Console<0><Console><Console>" changed map to "szf_atlantic_a4" (input "szf_atlantic_a4")

Stack Trace