Use internal Url struct in favor of url::Url to minimize the url dep in payjoin

[benalleng]

Relates to #1124

This adds the internal Url Struct to no longer depend on the url crate directly for it.

in addition I also transitioned to the http crate instead of the bhttp/http dep as that also depends on url internally.

However we still have reqwest inside payjoin url from payjoin-directory and test-utils which pull in the url dep.

I have also added a fuzz target, which already helped me better shape the parse function better.

I have only ran the fuzzer for a limited amount of time however and some more cpu hours might be helpful

Claude really helped me get through the brunt of this.

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[coveralls]

Pull Request Test Coverage Report for Build 22596246534

Details

• 314 of 376 (83.51%) changed or added relevant lines in 15 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.03%) to 82.512%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
payjoin-cli/src/app/v1.rs	1	2	50.0%
payjoin-cli/src/app/v2/ohttp.rs	5	6	83.33%
payjoin/src/core/ohttp.rs	2	3	66.67%
payjoin-cli/src/app/config.rs	4	6	66.67%
payjoin/src/core/io.rs	1	3	33.33%
payjoin/src/core/url.rs	286	341	83.87%

Files with Coverage Reduction	New Missed Lines	%
payjoin-cli/src/app/v1.rs	1	69.04%

Totals
Change from base Build 22579575348:	0.03%
Covered Lines:	10913
Relevant Lines:	13226

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💛 - Coveralls

[benalleng]

Drafting for mutants