Semantically reconcile modules-first/RPC coordinator PR #54 onto current infra main #58

PR #54 was validated on its prior base, but #55 (Terraform root-vs-child layout) and #56 (Supabase consolidation) have now advanced main, and GitHub reports #54 as non-mergeable.

Task:

• rebuild infra: modules-first environments and RPC Durable Object coordinator #54 on current main without force/rebase-only conflict resolution;
• preserve modules/ as the provider-native root, environments/{preview,staging,production}, .ores-infra.toml, reusable Cloudflare Terraform helpers, and the SQLite-backed RPC Durable Object coordinator;
• preserve all infra: enforce Terraform root vs child module layout #55 layout rules and infra: fold zed-supabase into zed-infra #56 Supabase consolidation exactly;
• avoid bundling the unrelated workers/ vulnerability remediation tracked separately;
• use semantic conflict resolution and retain useful lineage from the existing branch.

Acceptance: current-main diff is reviewable, infra-layout-validate is stepfully green, Terraform fmt/init/validate passes, Wrangler type generation/dry-run passes, and no provider configuration is duplicated between root and child modules.