fix: fix ENABLE_ACTION_PROCESSING logic

[oxSaturn]

Relates to:

Risks

Low

Background

Setting ENABLE_ACTION_PROCESSING=true in .env file won't work at the moment as parseBooleanFromText doesn't handle true value but YES, NO etc. per:

https://github.com/ai16z/eliza/blob/main/packages/core/src/tests/parsing.test.ts#L36-L52

What does this PR do?

Update the code so ENABLE_ACTION_PROCESSING would work as expected.

What kind of change is this?

Documentation changes needed?

Testing

Where should a reviewer start?

Detailed testing steps

[odilitime]

note this also changes the default to off

[oxSaturn]

note this also changes the default to off

It's set to false in .env.example https://github.com/ai16z/eliza/blob/main/.env.example#L70. Do we want to enable it by default?

[odilitime]

I'm checking with Dorian, we'll roll with this until he explains why someone would want it on vs off