feat: improved preemtive rate limit for file transactions

[quiet-node]

Description:
A preemptive rate limit was introduced as a hotfix in version 0.52.1, using a logic that preemptively rate-limited file transactions by comparing a hard-coded amount of tinybars that was assumed to be the cost for FileCreate and FileAppend transactions. However, this logic was incorrect and the tinybar amount was a random figure agreed among the team for the purposes of the hotfix.

This PR improves the rate-limiting logic by leveraging the Hedera Fee Calculator to estimate fees for FileCreate and FileAppend transactions based on a file size of FILE_APPEND_CHUNK_SIZE bytes. This approach ensures the estimated fees more closely align with the actual transaction fees charged for these transactions.

Fixes #2921

Notes for reviewer:

Checklist

• Documented (Code comments, README, etc.)
• Tested (unit, integration, etc.)

[github-actions]

Acceptance Tests

  20 files  274 suites   34m 4s ⏱️
605 tests 597 ✔️ 4 💤 4 ❌
811 runs  801 ✔️ 4 💤 6 ❌

Results for commit a431881.

♻️ This comment has been updated with latest results.

[github-actions]

Tests

       3 files     297 suites   19s ⏱️
1 353 tests 1 352 ✔️ 1 💤 0 ❌
1 362 runs  1 361 ✔️ 1 💤 0 ❌

Results for commit a431881.

♻️ This comment has been updated with latest results.

[victor-yanev]

Looks good, a couple of questions and nits

[ebadiere]

LG.

[victor-yanev]

Btw, when I come to think about those fees we use from the hedera fee calculator - aren't those estimates for the whole fee of the transaction? What part of that is paid by the relay operator? Isn't most of that paid by the signer of the transaction? Are you sure that those estimates reflect what is actually being paid by the relay operator - please add an acceptance test that verifies the estimates are accurate by comparing the difference in the operator's balance after performing the transaction to the result from the estimateFileTransactionFee.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

Attention: Patch coverage is 97.50000% with 1 line in your changes missing coverage. Please review.

Project coverage is 89.92%. Comparing base (ef3dd83) to head (a431881).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/relay/src/lib/eth.ts	91.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2922      +/-   ##
==========================================
+ Coverage   89.32%   89.92%   +0.59%     
==========================================
  Files          56       58       +2     
  Lines        3832     3900      +68     
  Branches      774      779       +5     
==========================================
+ Hits         3423     3507      +84     
+ Misses        362      346      -16     
  Partials       47       47              

Flag	Coverage Δ
relay	90.14% <97.50%> (+0.38%)	⬆️
server	88.15% <ø> (+0.89%)	⬆️
ws-server	100.00% <ø> (?)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
packages/relay/src/lib/clients/mirrorNodeClient.ts	95.65% <100.00%> (+<0.01%)	⬆️
packages/relay/src/lib/clients/sdkClient.ts	65.81% <100.00%> (+3.05%)	⬆️
packages/relay/src/lib/constants.ts	91.11% <100.00%> (+0.20%)	⬆️
packages/relay/src/lib/errors/JsonRpcError.ts	74.50% <ø> (ø)
packages/relay/src/lib/hbarlimiter/index.ts	100.00% <100.00%> (+1.61%)	⬆️
packages/relay/src/lib/eth.ts	88.96% <91.66%> (+0.14%)	⬆️

... and 4 files with indirect coverage changes