Constant M3_PLACEMENT_KEY_ESTRATEGIA 

pub const M3_PLACEMENT_KEY_ESTRATEGIA: &str = "estrategia";

Canonical camelCase YAML sub-key for the crate::aplicacao::Placement struct’s estrategia distribution-strategy discriminator — the per-M3_KEY_PLACEMENT-block field the M3 crate::aplicacao::PlacementStrategy enum’s Serialize derive emits, and the exact scalar every downstream consumer dispatches on:

• the lareira-fleet-programs aggregator’s per-entry strategy dispatch (each programs[].placement.estrategia reads "SingleNode" / "Replicated" / "Sharded" verbatim to select the takeover semantics per MESH-COMPOSITION.md §II.1),
• the future app-operator reconciler’s per-Aplicacao strategy branch,
• the future mesh.pleme.io/v1alpha1/Aplicacao CR materializer’s admission-time spec.placement.estrategia typed-enum bind,
• and every M3 Adaptive weighting the compression pass reads off placement.estrategia per MESH-COMPOSITION.md §V.

The scalar is derived by crate::aplicacao::Placement’s #[serde(rename_all = "camelCase")] from the Rust field name estrategia; estrategia has no _, so the serde transform is a no-op on this axis and the emitted key equals the source-side field name byte-for-byte. Lifting the byte to one &'static str closes the drift footgun structurally: a future refactor renaming the Rust field (estrategia → strategy for English-uniformity, distribution for schema-clarity, etc.) OR retaining the field name while adding a #[serde(rename = "…")] override would silently emit a placement: block whose distribution-strategy discriminator lands under one key while every downstream consumer still probes another — the aggregator’s dispatch, the operator’s reconcile, the CR materializer’s admission bind would each silently no-op, and the workload would silently come up under the strategy’s serde-derived default rather than the per-Aplicacao override the typed slot set. The identity pin + serde round-trip pin the sweep introduces catch the drift at caixa-core / caixa-mesh build time rather than at the aggregator’s filter step or the operator’s reconcile posture, far from the rebrand commit’s source.

Peer of M3_KEY_PLACEMENT on the same programs.yaml per-entry axis — that constant names the top-level overlay key the entry carries, this one names the per-placement: sub-block strategy discriminator every consumer dispatches on. Byte-identical to (but semantically distinct from) crate::supervisor::SupervisorSpec’s peer estrategia field on the M2 supervisor-strategy axis — that axis carries crate::supervisor::RestartStrategy (OneForOne / OneForAll / RestForOne / SimpleOneForOne, OTP supervisor semantics) while this axis carries crate::aplicacao::PlacementStrategy (SingleNode / Replicated / Sharded, cross-cluster distribution semantics); splitting the two lets each schema’s future rebrand land independently on the same byte-identical-but-semantically- distinct discipline the FLEET_PROGRAMS_KEY_NAME / KUBE_KEY_NAME split established.