fix(deps): Optionally enable op feature for reth-optimism-primitives

[emhane]

Closes #241

The op feature exists in reth to be able to implement traits defined in reth on op-alloy types. The intermediary trie nodes store doesn't use those op-alloy-types, it operates on hashed data

Ref paradigmxyz#19018

[Copilot]

Pull Request Overview

This PR fixes dependency management for the reth-optimism-primitives crate by introducing an optional op feature. The changes ensure consistent feature enablement across the codebase when working with Optimism-specific functionality.

• Introduced a new op feature to reth-optimism-primitives crate
• Updated dependency declarations to optionally enable the op feature where needed
• Added feature guards to implementation code to prevent compilation issues when the feature is disabled

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/optimism/primitives/Cargo.toml	Adds new op feature and updates dependency specifications
crates/optimism/primitives/src/lib.rs	Adds feature guard for NodePrimitives implementation
crates/storage/db-api/Cargo.toml	Updates feature dependency to optionally enable op feature
crates/rpc/rpc-convert/Cargo.toml	Updates feature dependency to optionally enable op feature
crates/optimism/node/Cargo.toml	Removes hardcoded reth-codec feature dependency
crates/optimism/evm/Cargo.toml	Explicitly enables op feature for required dependencies

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[emhane]

realised that TrieUpdates need serde-bincode-compat sometimes...so does reth-exex indirectly via reth-exex-types. so I'm adding the feature to reth-trie too, meaning this pr will take a wee bit longer ... @dhyaniarun1993

[emhane]

closing in favour or #250