docs: Transaction consensus rules: Size rules

[oxarbitrage]

Motivation

Document the transaction consensus rules. This pull request is about a category of them that we called transaction size rules. Will close #3426 if merged.

Solution

Document all the rules in the ticket, remove extra documentation and try to leave where possible just one text for each consensus rule.

Review

Anyone can review.

Reviewer Checklist

• Consensus rule docs are in a good spot.
• All the rules in the ticket were added or modified in this PR.
• No piece of doc comment that i want to keep was deleted.

Follow Up Work

The other 2 sections of the transaction consensus rules which are in the following issues:

• Document consensus rules from Zcash spec 7.1.2: Coinbase transactions #3427
• Document consensus rules from Zcash spec 7.1.2: Shielded pools #3428

[oxarbitrage]

I was not able to found this rule :

[Pre-Sapling] The encoded size of the transaction MUST be less than or equal to 100000 bytes.

We probably don't implement it because we checkpoint but i was wondering if this should be quoted anyway somewhere in the code with a note on why it is not enforced.

[teor2345]

I was not able to found this rule :

[Pre-Sapling] The encoded size of the transaction MUST be less than or equal to 100000 bytes.

We probably don't implement it because we checkpoint but i was wondering if this should be quoted anyway somewhere in the code with a note on why it is not enforced.

I suggest quoting it where we enforce the block size limit on transactions. (Since transactions must get mined into a block to be useful, we reject transactions that are larger than blocks.)

[codecov]

Codecov Report

Merging #3461 (dcf7bac) into main (499ae89) will increase coverage by 0.15%.
The diff coverage is 77.02%.

❗ Current head dcf7bac differs from pull request most recent head 0ca6751. Consider uploading reports for the commit 0ca6751 to get more accurate results

@@            Coverage Diff             @@
##             main    #3461      +/-   ##
==========================================
+ Coverage   78.34%   78.49%   +0.15%     
==========================================
  Files         267      273       +6     
  Lines       31526    31779     +253     
==========================================
+ Hits        24698    24946     +248     
- Misses       6828     6833       +5     

[oxarbitrage]

Thank you @teor2345 , i quoted the missing rule with some notes at 4089e5a

[conradoplg]

Looks good, I've checked all rules and only have a question about the last one

[teor2345]

This PR failed due to an unrelated timing issue in the acceptance tests:

---- zebra_zcash_listener_conflict stdout ----
Error:
0: conflicted node2 was still running, but the test expected a panic

https://github.com/ZcashFoundation/zebra/runs/5099762771?check_suite_focus=true#step:13:1742

I don't think we have a ticket for this failure, I haven't seen it in months.

Edit: this is now #3489

[teor2345]

Thanks, looks good to me!

[conradoplg]

Looks good! Nightly test is failing, not sure if it's intermittent, I'll retry it