feat: set no-op router to EvidenceKeeper for evmd

[zsystm]

Description

This PR sets an empty evidencetypes.Router to the EvidenceKeeper when constructing the reference evmd app.

Context

The evmd app aims to support all precompiles as a reference implementation. However, the current setup lacks a router configuration for EvidenceKeeper, which causes a nil panic when invoking SubmitEvidence from the evidence precompile.

Moreover, the Evidence precompile isn't even enabled in local_node.sh by default, meaning it's not currently part of the standard local testing flow.

Even if we add the Evidence precompile to the runtime, it cannot function properly without a router set in EvidenceKeeper, making any E2E flow impossible at the moment.

Fix

• Enable slashing and evidence precompiles in local_node.sh
• Initializes a router with noOpEvidenceHandler and assigns it to the EvidenceKeeper in app.go. This allows the SubmitEvidence to be executed without panic and enables E2E testing for the evidence flow.
• Addresses an argument parsing issue with the Equivocation struct: passing the argument using the exact Go struct format works in Go-based tests, but fails in E2E tests using this Hardhat script.

Closes: #275

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[vladjdk]

Lgtm, let's think about a permanent fix or whether we should remove the Evidence precompile entirely. @aljo242 pinging you here for visibility.

[zsystm]

@vladjdk
Personally, I’m not sure the Evidence precompile is worth keeping. It’s generally good to support more features, but in this case, I haven’t seen chains actually using evidence routers on the app side. So I’m leaning toward removing it, since the practical value seems low.

cc: @cloudgray