Provide a debug api flag for bundler api

[zsluedem]

I want to continue the question #43 (comment) here.

Currently, our debug API is config with a compiling flag #[cfg(debug_assertions)] which means the debug api would be there only when we build with cargo build. If we want to build with release version cargo build --release with compiler optimization, there are no debug apis.

I suggest we using the method like geth does providing a flag like --api debug to enable debug api instead of put it as a compilation flag. In that way, we could use release version to run tests especially for https://bundler-test-results.eip4337.com/. (BTW, @Vid201 very great job on it.) I want to see whether we could beat stackup-bundler on performance.

@Vid201 What do you think?

[Vid201]

Agree 100 % percent.

After some testing and thinking about that, I agree it's better to add additional flag like geth to enable certain API endpoints.

[Vid201]

And we can provide two packages on the repo - one with enabled debug api (for testing) and one without.