feat(cable): add extensive television cable channel configurations and related files

television/cable/env.toml

@@ -0,0 +1,22 @@
+[metadata]
+name = "env"
+description = "A channel to select from environment variables"
+
+[source]
+command = "printenv"
+output = "{split:=:1..}" # output the value
+
+[preview]
+command = "echo '{split:=:1..}'"
+
+[ui]
+layout = "portrait"
+preview_panel = { size = 20, header = "{split:=:0}" }
+
+[keybindings]
+shortcut = "f3"
+
+[actions.name]
+description = "Output the variable name instead of the value"
+command = "echo '{split:=:0}'"
+mode = "execute"