✨ Multi cluster controller sharding

[zachsmith1]

What

Deterministic sharding via HRW (rendezvous) over live peers.
Peer leases mcr-peer-* (membership/weights) + shard leases mcr-shard- (per-cluster fencing, single writer).
Clean handoff: watches detach/re-attach on ownership change.
Rebalance on scale up/down.

Why

Prevent double reconciles & cold-start stampede.
Balanced, deterministic ownership with fast failover.

How to try

Follow the README (examples/sharded-namespace) for build/deploy/observe steps.

Changes

Manager: HRW + per-cluster Lease fencing, peer/fence prefix split.
Controller: per-cluster engagement context, re-engage fix.
Source: removable handler, re-register on new ctx.

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[linux-foundation-easycla]

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• ✅login: zachsmith1 / name: Zach Smith / (f3ea62f, 1db63bc, ed2a440)
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• ✅login: zachsmith1 / name: Zach Smith / (f3ea62f, 1db63bc, ed2a440, 0abdcad, 1493d97, 8c521f9, 434aeb5, c1bd6b3, 0a6a229, 335a35b, 83c6d32, 9181aba)
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[FourFifthsCode]

this looks amazing 🚀

with this implementation, is it possible to shard individual clusters too or is it per cluster?

[zachsmith1]

this looks amazing 🚀

with this implementation, is it possible to shard individual clusters too or is it per cluster?

This is just for clusters but I think there is another community project we could leverage for the intra cluster sharding