Add OP_INTERNALKEY for Tapscript #29269

1. 
   reardencode commented at 6:18 am on January 18, 2024: none

   This pull request forks from #29198 and includes only OP_INTERNALKEY and its tests.
2. 
   DrahtBot commented at 6:18 am on January 18, 2024: contributor

   The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

   Code Coverage

   For detailed information about the code coverage, see the test coverage report.

   Reviews

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   Type	Reviewers
   Concept ACK	moonsettler

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   Conflicts

   Reviewers, this pull request conflicts with the following ones:

   • #31519 (refactor: Use std::span over Span by maflcko)
   • #31460 (fuzz: Expand script verification flag testing to segwit v0 and tapscript by dergoegge)
   • #29270 (Implement OP_CHECKSIGFROMSTACK(VERIFY) by reardencode)
   • #29247 (CAT in Tapscript (BIP-347) by 0xBEEFCAF3)

   If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

3. DrahtBot added the label CI failed on Jan 18, 2024
4. 
   moonsettler commented at 1:14 pm on January 19, 2024: none

   Concept ACK!
5. glozow added the label Consensus on Feb 5, 2024
6. Add OP_INTERNALKEY for Tapscript

   Testing is minimal, but so is the code.

   85206c238d
7. reardencode force-pushed on Apr 25, 2024

Contributors
reardencode DrahtBot moonsettler

Labels
Consensus CI failed