fix: verifier request schema (#4326)

## What ❔

Two changes to the verification request schema:

1. Change the type of the optimizer runs from `u16` to `usize`. This
allows values larger than 65535 to be passed and matches foundry's type
for the field.

2. Add a default value for `optimization_used`. Currently, it's tedious
that even for the JSON standard verification request, this field is
required but ignored.

Additionally, there is a DB migration to requeue some Etherscan
verifications, as Etherscan has fixed the issues on their end.

## Why ❔

<!-- Why are these changes done? What goal do they contribute to? What
are the principles behind them? -->
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own ZK Chain -->
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1. Currently, there is no way to submit a request using the single file
format with optimizer runs greater than 65535.
2. To provide a better UX when working with the verification endpoint.
3. To verify contracts on Etherscan that previously failed due to bugs
in their API.

## Is this a breaking change?
- [ ] Yes
- [X] No

## Operational changes
<!-- Any config changes? Any new flags? Any changes to any scripts? -->
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ZK Chain may need to know -->

## Checklist

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- [X] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [X] Tests for the changes have been added / updated.
- [ ] Documentation comments have been added / updated.
- [X] Code has been formatted via `zkstack dev fmt` and `zkstack dev
lint`.

Author: vasyl-ivanchuk

core/lib/contract_verifier/src/tests/real.rs

@@ -226,7 +226,10 @@ async fn using_standalone_solc(specify_contract_file: bool) {
 
 #[test_casing(3, [(Some(100), None), (None, Some("shanghai")), (Some(200), Some("paris"))])]
 #[tokio::test]
-async fn using_standalone_solc_with_custom_settings(runs: Option<u16>, evm_version: Option<&str>) {
+async fn using_standalone_solc_with_custom_settings(
+    runs: Option<usize>,
+    evm_version: Option<&str>,
+) {
     let (compiler_resolver, supported_compilers) = real_resolver!();
 
     let version = &supported_compilers.solc;

core/lib/dal/migrations/20250603180631_requeue_failed_etherscan_verifications.down.sql

@@ -0,0 +1 @@
+-- Add down migration script here

core/lib/dal/migrations/20250603180631_requeue_failed_etherscan_verifications.up.sql

@@ -0,0 +1,12 @@
+-- Requeue failed Etherscan verification requests after Etherscan has fixed the underlying issue.
+-- We have just a few failed requests, so the performance of the query is not a concern.
+UPDATE etherscan_verification_requests
+SET 
+	status = 'queued',
+	etherscan_verification_id = NULL,
+	processing_started_at = NULL,
+	error = NULL,
+	attempts = 0
+WHERE error LIKE '%Source code exceeds max accepted (500k chars) length%'
+    OR error LIKE '%Invalid or not supported solc version%'
+    OR error LIKE '%Invalid zksolc version%';

core/lib/types/src/contract_verification/api.rs

@@ -136,6 +136,7 @@ pub struct VerificationIncomingRequest {
     pub contract_name: String,
     #[serde(flatten)]
     pub compiler_versions: CompilerVersions,
+    #[serde(default)]
     pub optimization_used: bool,
     /// Optimization mode used for the contract. Semantics depends on the compiler used; e.g., for `vyper`,
     /// allowed values are `gas` (default), `codesize` or `none`.
@@ -201,7 +202,7 @@ pub struct VerificationEvmSettings {
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub evm_version: Option<String>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub optimizer_runs: Option<u16>,
+    pub optimizer_runs: Option<usize>,
 }
 
 #[derive(Debug, Eq, PartialEq, Clone, Copy)]