* feat(rpc): gate internode legacy signature fallback behind a convergence counter and strict env
Add the backlog#1327 Plan-A rollout infrastructure on top of the already-merged v2 target-bound internode gRPC authentication: a rustfs_system_network_internode_signature_v1_fallback_total counter that increments only when a request without any v2 auth headers is accepted through the legacy constant-target signature, and a RUSTFS_INTERNODE_RPC_SIGNATURE_STRICT env (default false, compile-time asserted) that, when enabled later, closes the legacy fallback path. Default behavior is fail-open and byte-identical for legacy-only peers; requests carrying v2 headers are verified as v2 with no downgrade exactly as before.
Refs https://github.com/rustfs/backlog/issues/1327
* ci: fix internode auth test lint failures
* perf(ecstore): cache internode sig strict env
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Co-authored-by: houseme <housemecn@gmail.com>
Zhengchao An
ffd1b94e1f