feat: add support for secp256r1 and replace libsecp256k1

[obycode]

Implementing #6554.

[jcnelson]

Why are we dropping libsecp256k1 in favor of the one from RustCrypto? The former has been extensively audited and is used by Bitcoin.

[obycode]

Why are we dropping libsecp256k1 in favor of the one from RustCrypto? The former has been extensively audited and is used by Bitcoin.

The thought was that since we're pulling in the RustCrypto crate for secp256r1, we may as well also replace the k256 crate as well with this Rust-native solution that seems to be well-vetted and audited as well. libsecp256k1 is a wrapped C library.

[jcnelson]

I think you have a few codec bugs that need to be fixed before merging.

[codecov]

Codecov Report

❌ Patch coverage is 49.05923% with 731 lines in your changes missing coverage. Please review.
✅ Project coverage is 52.59%. Comparing base (9dfb1d1) to head (f9a3f69).
⚠️ Report is 54 commits behind head on develop.

Files with missing lines	Patch %	Lines
stacks-common/src/util/secp256k1.rs	57.56%	261 Missing ⚠️
...ity/src/vm/analysis/type_checker/v2_1/tests/mod.rs	0.62%	159 Missing ⚠️
stacks-common/src/util/secp256r1.rs	54.34%	142 Missing ⚠️
clarity/src/vm/tests/crypto.rs	46.50%	130 Missing ⚠️
clarity/src/vm/functions/crypto.rs	63.38%	26 Missing ⚠️
stacks-signer/src/signerdb.rs	0.00%	4 Missing ⚠️
clarity/src/vm/costs/costs_2.rs	0.00%	3 Missing ⚠️
clarity/src/vm/costs/costs_2_testnet.rs	0.00%	3 Missing ⚠️
clarity/src/vm/costs/costs_3.rs	0.00%	3 Missing ⚠️

❌ Your project status has failed because the head coverage (52.59%) is below the target coverage (80.00%). You can increase the head coverage or adjust the target coverage.

❗ There is a different number of reports uploaded between BASE (9dfb1d1) and HEAD (f9a3f69). Click for more details.

HEAD has 57 uploads less than BASE

Flag	BASE (9dfb1d1)	HEAD (f9a3f69)
	133	76

Additional details and impacted files

@@             Coverage Diff              @@
##           develop    #6581       +/-   ##
============================================
- Coverage    79.82%   52.59%   -27.23%     
============================================
  Files          571      573        +2     
  Lines       351696   352704     +1008     
============================================
- Hits        280724   185497    -95227     
- Misses       70972   167207    +96235     

Files with missing lines	Coverage Δ
clarity/src/vm/analysis/arithmetic_checker/mod.rs	92.48% <100.00%> (ø)
clarity/src/vm/analysis/read_only_checker/mod.rs	88.28% <ø> (-0.40%)	⬇️
.../src/vm/analysis/type_checker/v2_05/natives/mod.rs	80.30% <ø> (-9.17%)	⬇️
...y/src/vm/analysis/type_checker/v2_1/natives/mod.rs	88.09% <100.00%> (-0.12%)	⬇️
clarity/src/vm/costs/cost_functions.rs	100.00% <100.00%> (ø)
clarity/src/vm/costs/costs_1.rs	100.00% <100.00%> (ø)
clarity/src/vm/costs/costs_4.rs	92.46% <100.00%> (-7.54%)	⬇️
clarity/src/vm/docs/mod.rs	70.76% <100.00%> (-19.97%)	⬇️
clarity/src/vm/functions/mod.rs	96.33% <100.00%> (-0.87%)	⬇️
clarity/src/vm/tests/mod.rs	52.80% <ø> (-5.62%)	⬇️
... and 13 more

... and 414 files with indirect coverage changes

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[github-actions]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.