build: bump `CLIENT_VERSION_MAJOR` to 30 #33347

1. 
   fanquake commented at 10:00 AM on September 9, 2025: member

   Last step before branch off.

2. build: bump CLIENT_VERSION_MAJOR to 30 9f744fffc3
3. DrahtBot added the label Build system on Sep 9, 2025
4. 
   DrahtBot commented at 10:00 AM on September 9, 2025: contributor

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   Code Coverage & Benchmarks

   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/33347.

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5. fanquake added this to the milestone 30.0 on Sep 9, 2025
6. hebasto approved
7. 
   hebasto commented at 10:13 AM on September 9, 2025: member

   ACK 9f744fffc39d93c9966dec1d61f113a7521983ad.

8. fanquake merged this on Sep 9, 2025
9. fanquake closed this on Sep 9, 2025

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10. fanquake deleted the branch on Sep 9, 2025

Milestone
30.0