FloatParam is not parsing env var properly

[vpusher]

I have been working with Python Cloud Functions for Firebase for a few weeks now and we are having an issue when it comes to float params with FloatParam.

Basic code to reproduce:

# .env
MY_FLOAT=0.0

# main.py
from firebase_functions.params import FloatParam
import firebase_admin

firebase_admin.initialize_app()

my_float = FloatParam("MY_FLOAT").value

From that setup, I have 2 issues:

1. The first one is that params types (string, int, boolean, float ...) cannot be read outside of a function implementation (i.e functions annotated with @tasks_fn.on_task_dispatched or @https_fn.on_call for example)
2. Second one is, whenever I move the reading part inside of Callable/Queue function implementation, my env var value got wrapped into an array (only for float params), then I got the following error when the CF tries to start up in Cloud Run:

File "/layers/google.python.pip/pip/lib/python3.12/site-packages/firebase_functions/params.py", line 353, in value
    return float(_os.environ[self.name])
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: could not convert string to float: '["0.0"]'

NB: That "array wrapping" behaviour for floats is not happening locally with emulators.