consensus: move amount.h into consensus #22951

A first step (of a few) towards some source code reorganization, as well as making libbitcoinconsensus slightly more self contained.

Related to #15732.

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #23155 (rpc: various fixups for dumptxoutset by jamesob)
• #23137 (Move-only: bloom to src/common by MarcoFalke)
• #23004 (multiprocess: Run external signer in wallet not node process by ryanofsky)
• #22918 (rpc: Add level 3 verbosity to getblock RPC call (#21245 modified) by kiminuo)
• #15606 (assumeutxo by jamesob)
• #15294 ([moveonly] wallet: Extract RipeMd160 by Empact)

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.

Concept ACK. I think this is organizationally the right thing to do. Nearly everything in amount.h is consensus critical:

• type CAmount
• constant MAX_MONEY
• function MoneyRange

Even COIN, though it strictly is a presentation detail, is used in src/validation.cpp to set the initial subsidy. So changing it would be consensus critical.

Concept ACK.

ACK 2c1554a10940e471708d0d81bde0d490dc1c73b4.

I see the last two commits as a way to modernize amount.h. Here are some additional suggestions:

• use type alias instead of typedef
• use separators for integer literals
• s/nValue/value/ to follow our name convention
• pass CAmount as a non-reference parameter: s/const CAmount&/CAmount/. Also #23076 (comment).

Concept ACK

concept ACK 9d0379cea6c164610d05287ae6dd4e66f35b92b 🏝

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