feat: update the exposed hardfork API to match Hardhat's definition

[anaPerezGhiglia]

Closes #1634.

Now that the hardfork type is owned by EDR (#1601) instead of mirroring revm's SpecId, we can shape the exposed API freely: this PR aligns it with Hardhat's own hardfork definitions, which will enable removing the conversion layers in Hardhat that translate between Hardhat and EDR names on every boundary crossing.

Breaking changes (TS API)

• Renamed the SpecId enum to L1Hardfork, mirroring OpHardfork. Discriminants are unchanged.
• Removed the pre-Byzantium L1 hardforks at the type level (Frontier, FrontierThawing, Homestead, DaoFork, Tangerine, SpuriousDragon). Forking a chain from a block that precedes its oldest supported hardfork now fails with an error naming that hardfork, instead of silently skipping hardfork validation.
• Renamed the hardfork name strings to Hardhat's camelCase definitions (e.g. "Byzantium" → "byzantium", "MuirGlacier" → "muirGlacier", "Bedrock" → "bedrock"). l1HardforkToString/opHardforkToString return the new names; l1HardforkFromString/opHardforkFromString and provider configs accept only them.
• Removed the exported hardfork name string constants (BYZANTIUM, …, AMSTERDAM, BEDROCK, …, ISTHMUS). Hardhat 3 imports them only in two test files; Hardhat 2 uses them in convertToEdr.ts, which already requires a rewrite for the changes above. Suggested instead to replace then with the corresponding enumToString function. E.g.: replace OSAKA with l1HardforkToString(L1Hardfork.Osaka)

Internal changes

• The name strings are derived from the variants via a single #[strum(serialize_all = "camelCase")] directive, replacing the per-variant serialize overrides. The expected strings are pinned as literals in each crate's name_round_trip test, which is the guard against unintended renames.
• Removed the hardfork::name string-constant modules from edr_chain_l1 and edr_op.
• The napi enums (L1Hardfork, OpHardfork) delegate parsing and string conversion to the domain types. The napi OpHardfork excludes Jovian/Interop, which are not exposed over N-API yet; its parse rejects them explicitly. Unit tests pin that the hand-written conversion tables between the napi and domain enums are inverses.

Notes for reviewers

• The napi-layer Rust enum is now also named L1Hardfork, colliding grep-wise with edr_chain_l1::L1Hardfork (the OP side already had this collision). An alternative is a role-based Rust name (e.g. ExposedL1Hardfork) with #[napi(js_name = "L1Hardfork")], keeping the TS API unchanged - open for discussion.

Hardhat migration

Hardhat's L1HardforkName/OpHardforkName values are now exactly EDR's hardfork strings, so the string-conversion mappings in HH3's convert-to-edr.ts and HH2's convertToEdr.ts can collapse to pass-throughs for supported forks.

[changeset-bot]

🦋 Changeset detected

Latest commit: da7670b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@nomicfoundation/edr	Minor

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[codecov]

Codecov Report

❌ Patch coverage is 88.88889% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.05%. Comparing base (def04e7) to head (da7670b).

Files with missing lines	Patch %	Lines
crates/edr_napi/src/chains/l1.rs	91.52%	4 Missing and 1 partial ⚠️
crates/edr_napi/src/chains/op.rs	80.76%	3 Missing and 2 partials ⚠️
crates/tool/op_chain_config_generator/src/main.rs	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1645      +/-   ##
==========================================
+ Coverage   79.97%   80.05%   +0.08%     
==========================================
  Files         462      462              
  Lines       80509    80500       -9     
  Branches    80509    80500       -9     
==========================================
+ Hits        64384    64445      +61     
+ Misses      13896    13841      -55     
+ Partials     2229     2214      -15     

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[Copilot]

Pull request overview

This PR aligns EDR’s exposed L1 and OP hardfork APIs with Hardhat-compatible names and enums.

Changes:

• Renames SpecId to L1Hardfork and removes obsolete forks/constants.
• Switches hardfork strings to camelCase.
• Updates N-API conversions, tests, and pre-hardfork validation.

Blocking findings remain:

• Critical (1 vote): Checked-in Hardhat 2/3 patches still use outdated hardfork conversion layers and SpecId.
• Critical (1 vote): Removing legacy exports breaks the patched Hardhat 2 converter.
• Critical (2 votes): The OP chain config generator still capitalizes names before parsing, causing valid activations to be rejected.

Reviewed changes

Copilot reviewed 15 out of 16 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
crates/eips/1559/src/lib.rs	Updates hardfork test inputs.
crates/edr_op/src/hardfork.rs	Applies camelCase OP hardfork names.
crates/edr_napi/test/provider.ts	Migrates provider tests to L1Hardfork.
crates/edr_napi/test/logs.ts	Updates log provider configuration.
crates/edr_napi/test/hardforks.ts	Tests updated hardfork names and enums.
crates/edr_napi/test/gasReport.ts	Updates gas report configuration.
crates/edr_napi/src/chains/op.rs	Updates OP N-API conversions.
crates/edr_napi/src/chains/l1.rs	Adds the new L1 N-API enum and conversions.
crates/edr_napi/index.js	Updates generated JavaScript exports.
crates/edr_napi/index.d.ts	Updates TypeScript declarations.
crates/edr_chain_l1/src/hardfork.rs	Removes pre-Byzantium forks and renames strings.
crates/edr_chain_l1/src/chains.rs	Removes unsupported chain activations.
crates/chain/config/src/lib.rs	Adds oldest-hardfork lookup.
crates/blockchain/fork/src/lib.rs	Validates forks against supported history.
.changeset/wise-falcons-relate.md	Documents string API changes.
.changeset/mighty-poems-tickle.md	Documents enum and fork behavior changes.

Suppressed comments (1)

crates/edr_napi/src/chains/l1.rs:103

• The public type is now an L1 hardfork enum, but the doc comment carried over from SpecId still calls it an “Ethereum spec” identifier. This wording is also propagated to index.d.ts, so consumers see an inaccurate description of the new API; update it to say “Identifier for an Ethereum L1 hardfork.”

// N-API projection of [`edr_chain_l1::Hardfork`], which only exists to
// generate the TS enum; string conversions delegate to the domain type.
#[napi]
#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub enum L1Hardfork {

---

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[Copilot]

Pull request overview

Copilot reviewed 17 out of 19 changed files in this pull request and generated 3 comments.

Files not reviewed (1)

• pnpm-lock.yaml: Generated file

Suppressed comments (1)

patches/hardhat@2.28.4.patch:985

• The reverse conversion has the same Hardhat 2 compatibility problem: l1HardforkToString(L1Hardfork.Merge) produces merge, but callers of edrSpecIdToEthereumHardfork receive a HardforkName and Hardhat 2 expects mergeForkBlock for that member. Returning the EDR string directly violates the declared return contract for Merge; map this fork back to Hardhat's value or align the Hardhat enum first.

+  // EDR's hardfork names match Hardhat's, so no conversion is needed.
+  return l1HardforkToString(specId) as HardforkName;

[anaPerezGhiglia]

This is not part of this PR changes

[Copilot]

Pull request overview

Copilot reviewed 20 out of 22 changed files in this pull request and generated no new comments.

Files not reviewed (1)

• pnpm-lock.yaml: Generated file

[anaPerezGhiglia]

Draft HH PR associated to these changes: NomicFoundation/hardhat#8574

[Wodann]

Overall this looks good. However, I do have some suggestions w.r.t the wording of the changesets that I think should be applied to match our changelog, before merging.

Feel free to apply them locally and merge with re-approval; or ask me to have a quick look if you deem it necessary.

[Wodann]

Now that we support Display for HardforkT, can this use the Display instead of the Debug trait implementation?

Suggested change

	"Cannot fork {chain_name} from block {fork_block_number}. The block precedes {oldest_hardfork:?}, which is the chain's oldest supported hardfork."
	"Cannot fork {chain_name} from block {fork_block_number}. The block precedes {oldest_hardfork}, which is the chain's oldest supported hardfork."

[anaPerezGhiglia]

Not so easily. To use Display here we'd have to add a Display bound for HardforkT generic type of this enum, and since this error nests into ProviderError, the bound ripples through every generic consumer that renders provider errors.
Containing that ripple means adding Display to the ProtocolHardfork umbrella trait itself, which I think goes against the style guide from #1618: error-formatting bounds belong at usage sites.
So I'd keep Debug formatting here, unless we want to deliberately declare Display part of ProtocolHardfork's contract.