ExEx metrics panels

[onbjerg]

Describe the feature

We added metrics in #7340 and we should add panels for these

reth/crates/exex/src/manager.rs

Lines 26 to 34 in 81090da

	/// Metrics for an ExEx.
	#[derive(Metrics)]
	#[metrics(scope = "exex")]
	struct ExExMetrics {
	/// The total number of canonical state notifications sent to an ExEx.
	notifications_sent_total: Counter,
	/// The total number of events an ExEx has sent to the manager.
	events_sent_total: Counter,
	}

reth/crates/exex/src/manager.rs

Lines 118 to 130 in 81090da

	/// Metrics for the ExEx manager.
	#[derive(Metrics)]
	#[metrics(scope = "exex_manager")]
	pub struct ExExManagerMetrics {
	/// Max size of the internal state notifications buffer.
	max_capacity: Gauge,
	/// Current capacity of the internal state notifications buffer.
	current_capacity: Gauge,
	/// Current size of the internal state notifications buffer.
	///
	/// Note that this might be slightly bigger than the maximum capacity in some cases.
	buffer_size: Gauge,
	}

Additional context

No response

[mw2000]

Would love to take this on

[onbjerg]

Cool, thanks @mw2000! Let me know if you get stuck 😄 Do you have a rough timeline?

[mw2000]

Ideally this weekend! I'll take a first pass at it today in case I have more questions @onbjerg

[mw2000]

@onbjerg here's a first pass at it -> #7605

Pretty much used similar panels that we had for blockchain_tree_canonical_chain_height.

A bit green when it comes to grafana dashboards, but I was seeing the following on my end:

As opposed to what the blockchain_tree_canonical_chain_height panel looks like:

Is there a misconfig in the code for the exex panels somewhere? I'll also double check from my side in the meantime

[onbjerg]

No, the reason you don't have any data is because you don't have any extensions installed - this is expected.

It looks fine to me, can you also add panels for the manager metrics?

[mw2000]

@onbjerg that sounds good, let me go ahead and do that.

Added, and PR out of draft + ready to review