bump node-reth commit reference to ad9d2be for latest flash-block metrics

[sconeman]

Summary

The main branch of base/node-reth moved forward 2025-05-07 (commit ad9d2be3aeca48822c8a877470c0003696e8b4a5) adding Flash-block tracking and new metrics.
Because reth/Dockerfile still pins the older hash 3f3d846…, every fresh build aborts at the commit-verification step. This PR realigns the pinned COMMIT value to the new HEAD so the image builds cleanly again. ([GitHub]1, [GitHub]2)

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Changes

--- a/reth/Dockerfile
@@
-ENV VERSION=main
-ENV COMMIT=3f3d84634cb3fccd429a9df6ea039a77be2b907b
+ENV VERSION=main
+ENV COMMIT=ad9d2be3aeca48822c8a877470c0003696e8b4a5

No other logic or build flags were modified.

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Rationale

• Build stability – keeps the SHA check from failing on CI/Compose builds.
• Latest feature set – incorporates Flash-block index metrics introduced in ad9d2be.
• Minimal blast radius – one-line env update; no behavioral changes outside the re-vendored upstream commit.

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Testing

1. docker compose build --no-cache completes for both execution and node services.
2. Local container starts successfully with NODE_TYPE=base, confirming base-reth-node binary is present.
3. Verified metrics endpoint (/metrics) exposes new flashblocks_in_block gauge.

[cb-heimdall]

✅ Heimdall Review Status

Requirement	Status	More Info
Reviews	✅ 1/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 1 Sum 2

[wbnns]

Thanks!

[wbnns]

Refactoring in #460