Better string escaping

[DeanPDX]

See discussion in #19. String escaping could be better. For example:

# This currently works because we are checking for " #".
APP_URL="https://myapp.com/#someAnchor"
# This currently does NOT work, but with better string escaping it could.
APP_ACTION="Take a #"

The current implementation is pretty naive.

[DeanPDX]

See also:

https://github.com/motdotla/dotenv?tab=readme-ov-file#what-rules-does-the-parsing-engine-follow