[Fjord] Add FastLZ compression into L1CostFunc

[mdehoog]

Reopening #8635, targeting Fjord rather than Ecotone.

Description
We found that the FastLZ algorithm is a pretty good estimate for the actual results we'd see from zlib compressing the batches we write to L1 (albeit with a different scalar as the compression ratios aren't quite as good). See https://github.com/roberto-bayardo/compression-analysis and this sheet.

This PR introduces a flzCompress call into the GasPriceOracle. Companion op-geth PR is here: ethereum-optimism/op-geth#202

See specs update here: ethereum-optimism/specs#25

Tests

Added tests comparing compression results from solidity + golang.

Additional context

The current naive L1Cost approach:

l1fee = ((0s in calldata) * 4 + (1s in calldata) * 16 + 188) * l1BaseFee * 0.684

works pretty well on average, but penalizes very compressible txs (e.g.), and undercharges incompressible txs (e.g.). This change makes the L1CostFunc much fairer compared to real-world L1 costs.

[coderabbitai]

Walkthrough

The Ethereum network has seen updates to its gas price oracle and compression utilities to improve efficiency and accommodate network upgrades. A test for the gas price oracle ensures its proper function, while the oracle itself now accounts for new network chains, Fjord and Ecotone. Compression techniques are refined in the Solidity library to optimize gas usage. Lastly, a new cost calculation method using FastLZ compression is introduced for L1 transactions, signifying a shift in fee structures following the Fjord upgrade.

Changes

File Path	Change Summary
op-e2e/.../gas_price_oracle_test.go	Added TestGasPriceOracle to validate gas price oracle contract.
packages/.../src/L2/GasPriceOracle.sol	Updated with isFjord and isEcotone variables; new setFjord function; modified _getCalldataGas logic.
packages/.../src/libraries/Compression.sol	Included flzCompressLen function for gas-efficient data length retrieval.
specs/exec-engine.md	Added "Fjord L1-Cost fee changes" section detailing new L1 cost calculation via FastLZ compression.

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[codecov]

Codecov Report

Attention: 16 lines in your changes are missing coverage. Please review.

Comparison is base (0ea5e0b) 19.38% compared to head (4bd3fb2) 24.50%.
Report is 173 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #9053      +/-   ##
===========================================
+ Coverage    19.38%   24.50%   +5.12%     
===========================================
  Files          151      104      -47     
  Lines         5912     3750    -2162     
  Branches      1271      541     -730     
===========================================
- Hits          1146      919     -227     
+ Misses        4691     2785    -1906     
+ Partials        75       46      -29     

Flag	Coverage Δ
cannon-go-tests	62.56% <ø> (?)
chain-mon-tests	?
common-ts-tests	?
contracts-bedrock-tests	0.65% <0.00%> (-0.01%)	⬇️
contracts-ts-tests	?
core-utils-tests	?
sdk-next-tests	?

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

Files	Coverage Δ
packages/contracts-bedrock/src/L2/L1Block.sol	0.00% <0.00%> (ø)
...ckages/contracts-bedrock/src/L2/GasPriceOracle.sol	0.00% <0.00%> (ø)

... and 79 files with indirect coverage changes

[tynes]

Would super appreciate thorough specs with reasoning before any implementation is merged

[github-actions]

This PR is stale because it has been open 14 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[github-actions]

This PR is stale because it has been open 14 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[mdehoog]

Closing in favor of #9618, which uses a different base branch