Merge bitcoin/bitcoin#23293: doc: Add comment to COIN constant.

1946af2 Add comment to COIN constant. (Kennan Mell)

Pull request description:

  The COIN constant is critical in understanding Bitcoin's supply, but what it represents isn't clear from the name of the constant. Adding a comment clarifies the meaning of the constant for future readers.

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Tree-SHA512: ba27c6bd4a4c92664a71ef081104e9e50e47022d68eb955c247b7c49a0046a42bf64bf23a14563c646411b7be6027fea918cc62baa01bbf319b82d14d368f280

Author: laanwj

src/consensus/amount.h

@@ -11,6 +11,7 @@
 /** Amount in satoshis (Can be negative) */
 typedef int64_t CAmount;
 
+/** The amount of satoshis in one BTC. */
 static constexpr CAmount COIN = 100000000;
 
 /** No amount larger than this (in satoshi) is valid.