[finishes #70304186] when story is running -> repeat forever

Changed this event to look like a more traditional repeatForever block. It is not allowed to have statements attached below or above it. All statements must be attached within. Color is set to match other repeat blocks.

Actual execution of the attached code is unchanged - it still executes once per tick unless async block execution is pending.

Changed variable names internally to make it easier for maintenance. Levels created by users (internal only, of course) prior to this change may break because the block name changed :(

A dashboard commit was made to update the instruction text in puzzle 5 that referred to this block.