refactor: remove unused ser_writedata16be and ser_readdata16be #33093

1. 
   l0rinc commented at 11:28 pm on July 29, 2025: contributor

   Remove dead code from serialization logic - extracted from https://github.com/bitcoin/bitcoin/pull/31868
2. cleanup: remove unused `ser_writedata16be` and `ser_readdata16be` 0431a690c3
3. DrahtBot added the label Refactoring on Jul 29, 2025
4. 
   DrahtBot commented at 11:28 pm on July 29, 2025: contributor

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

   Code Coverage & Benchmarks

   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/33093.

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   ACK	jlest01, maflcko, achow101

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5. 
   jlest01 commented at 9:14 pm on July 30, 2025: none

   ACK https://github.com/bitcoin/bitcoin/pull/33093/commits/0431a690c3a498a1e728c9df34a132ac16177a04
6. 
   maflcko commented at 6:28 am on July 31, 2025: member

   lgtm ACK 0431a690c3a498a1e728c9df34a132ac16177a04
7. 
   achow101 commented at 11:01 pm on July 31, 2025: member

   ACK 0431a690c3a498a1e728c9df34a132ac16177a04
8. achow101 merged this on Jul 31, 2025
9. achow101 closed this on Jul 31, 2025

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10. l0rinc deleted the branch on Aug 1, 2025

Contributors
l0rinc DrahtBot jlest01 maflcko achow101

Labels
Refactoring