Update x402 docs

[dssei]

• Update x402 to use coinbase x402 packages since Sei is officially supported by x402
• Update all code examples

[changeset-bot]

⚠️ No Changeset found

Latest commit: 6921b53

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.29%. Comparing base (0dc3751) to head (6921b53).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #293   +/-   ##
=======================================
  Coverage   79.29%   79.29%           
=======================================
  Files          82       82           
  Lines        1280     1280           
  Branches      212      212           
=======================================
  Hits         1015     1015           
  Misses        259      259           
  Partials        6        6           

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[alexander-sei]

https://linear.app/seilabs/issue/REL-34/bug-in-sei-js-tutorial missing here, it still has npm in all tutorials

[dssei]

https://linear.app/seilabs/issue/REL-34/bug-in-sei-js-tutorial missing here, it still has npm in all tutorials

Which one do we want as a default? NPM worked for me, but I did not test in monorepos though. Do we want to remove it completely?

[dssei]

https://linear.app/seilabs/issue/REL-34/bug-in-sei-js-tutorial missing here, it still has npm in all tutorials

Which one do we want as a default? NPM worked for me, but I did not test in monorepos though. Do we want to remove it completely?

Made pnpm the default option

[Shreyas-sei]

Pnpm is good but yarn would be more recommendable as default