CHIA-2900 Fast forward mempool optimization

[AmineKhaldi]

Purpose:

Introduce a new state for the spent_index column in the coin_record table to track unspent coins that have the same puzzle hash and amount as their parents.

Current Behavior:

spent_index = 0 means a coin is unspent.

New Behavior:

spent_index = 0 means a regular coin is unspent, and spent_index = -1 means this unspent coin has the same puzzle hash and amount as its parent.

[arvidn]

We should have a plan for how to handle coins created before this change too

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[github-actions]

Conflicts have been resolved. A maintainer will review the pull request shortly.

[arvidn]

I don't expect that checking amount being odd is important. That's not going to bring a material speed-up (if one at a ll), right?

[coveralls-official]

Pull Request Test Coverage Report for Build 16166185982

Details

• 156 of 156 (100.0%) changed or added relevant lines in 5 files are covered.
• 29 unchanged lines in 7 files lost coverage.
• Overall coverage increased (+0.007%) to 91.395%

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Files with Coverage Reduction	New Missed Lines	%
chia/full_node/pending_tx_cache.py	1	96.55%
chia/rpc/rpc_server.py	1	89.16%
chia/wallet/wallet_node.py	1	87.67%
chia/server/node_discovery.py	4	81.75%
chia/server/server.py	4	82.51%
chia/server/address_manager.py	5	92.84%
chia/full_node/full_node.py	13	87.78%

Totals
Change from base Build 16149582872:	0.007%
Covered Lines:	102197
Relevant Lines:	111693

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💛 - Coveralls