Phase 1: Refactor Config for Archive Shape Management

The Option E''+S convergence means we DO NOT need a "shape" config for the active tier (e.g. chunked vs flat) since the syncers will uniformly use deterministic ID-chunking for the active tier and lazy ordinal chunking for the archive tier.

The Architectural Reality

We need to formalize an archive configuration in config.mjs (e.g. archiveRoot or similar) that sets up the single archive root. Crucially, AC1 must provide the configuration for the lazy ordinal chunking in the archive tier:

• archiveChunkThreshold: 100
• archiveChunkPrefix: 'chunk-' This ensures the chunking semantics are defined in the config layer, not hardcoded in the helpers/syncers.

The Fix

Introduce a unified archive path configuration in the environment/config substrate and ensure it is properly exposed for the sync services and path helpers to consume.

Acceptance Criteria

• Add archiveRoot to the canonical environment configuration (config.template.mjs).
• Add archiveChunkThreshold: 100 and archiveChunkPrefix: 'chunk-' to support lazy ordinal chunking in the archive tier.
• Ensure the new configuration is properly documented in the Deployment Cookbook if necessary.

Out of Scope

Modifying the archivePath helper (AC2) or the Syncers themselves (AC3-AC5). This ticket is strictly for the configuration foundation. Adding "shape" toggles for active tiers.

Origin Session ID

Origin Session ID: 57502eb2-7f7b-4b9b-a849-49f016b08c95 Retrieval Hint: "Epic 11187 Phase 1 Config Refactor"