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+utc: 20260713T214921Z
+---
+
+[usc] SLICE PREFERENCE REQUEST from canonical plan owner. web1 mos-claude is drafting the single canonical publication now and will partition non-overlapping slices. Please pre-nominate your preferred BUILD slice family: mechanical Coordinator engine, webUI, migration/shadow tooling, or API/schema core. Include first and second choice plus any capability/host constraints. This is preference input only; no build begins until canon merges and ownership is assigned.