Puzzle hash optimizations

[arvidn]

This PR is best reviewed one commit at a time.

Purpose:

This PR aims to improve the performance of computing puzzle hashes. This is achieved in 3 commits:

1. rather than computing the hash of [] on the fly, use the constant NULL_TREEHASH.
2. rather than constructing Program objects from values, just to compute the tree hash. Compute the tree hash directly from the values using the existing shatree_atom(), shatree_pair(), as well as introducing shatree_int() and shatree_byte_list()
3. Avoid computing the public key given a derived private key (get_g1()) multiple times, by wrapping calculate_synthetic_public_key and calculate_synthetic_secret_key in LRU caches.

Current Behavior:

We waste time in get_inner_puzhash_by_p2()

New Behavior:

We waste less time in get_inner_puzhash_by_p2()

profile

function	before	after	after / before
get_inner_puzhash_by_p2()	25.32%	5.16%	0.20
puzzle_hash_for_public_key_and_hidden_puzzle_hash	17%	2.12%	0.12

before

after

[richardkiss]

Looks good. Some minor nits.

[github-actions]

File	Coverage	Missing Lines
chia/wallet/did_wallet/did_wallet.py	60.0%	lines 534-535

Total	Missing	Coverage
51 lines	2 lines	96%

[coveralls-official]

Pull Request Test Coverage Report for Build 9023140534

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 49 of 51 (96.08%) changed or added relevant lines in 8 files are covered.
• 20 unchanged lines in 8 files lost coverage.
• Overall coverage increased (+0.04%) to 90.848%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
chia/wallet/did_wallet/did_wallet.py	3	5	60.0%

Files with Coverage Reduction	New Missed Lines	%
chia/_tests/simulation/test_simulation.py	1	96.5%
chia/daemon/server.py	1	83.21%
chia/introducer/introducer.py	1	78.26%
chia/timelord/timelord.py	2	73.67%
chia/full_node/full_node.py	2	85.25%
chia/rpc/rpc_server.py	3	87.67%
chia/server/node_discovery.py	3	81.03%
chia/wallet/wallet_node.py	7	88.51%

Totals
Change from base Build 9018383795:	0.04%
Covered Lines:	99018
Relevant Lines:	108945

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💛 - Coveralls