V2 lookbook: repair split-pack links and missing Loom explainers; reconcile final-state authorities

[ScriptedAlchemy]

Purpose and branch safety

Repair the authoritative concept handoff consumed by #1099 and #1100 without redrawing the accepted plates or changing production behavior. Track the work in this product repository; any product implementation PR targets codex/tracedecay-total-redesign-plan-reopened. Keep #707 DRAFT; do not merge or undraft it. Changes to the separate td-brain-demo export belong in an explicitly scoped follow-up there, not a silent write to its main branch.

Reviewed: ScriptedAlchemy/td-brain-demo@87e14dcd1026e63390233f56c795accee81b351e and ScriptedAlchemy/tracedecay@dd002654eb9ccc277eda0f9f4fe87ef1e6f0a660. Findings below come from repository trees and Markdown/source reads. Image metadata was verified, but PNG pixels could not be inspected in this review environment. This is an integrity/authority issue, not a claim that a plate looks wrong.

Verified defects

1. Demo gallery links use the product mirror's layout rather than the exported layout

lookbook/GALLERY.md links, for example, 01-brain/final/01-registry-overview.png and 03-loom/final/01-follow-loaded-tail.png.

The demo actually stores these files at:

• lookbook/pngs/01-brain/final/01-registry-overview.png
• lookbook/pngs/03-loom/final/01-follow-loaded-tail.png
• lookbook/pngs/03-loom/final/02-temporal-replay.png

There is no lookbook/01-brain or lookbook/03-loom directory at the reviewed commit. The demo gallery's image links therefore do not resolve. This finding is specific to the split demo export; the product mirror uses the co-located mockups/ui-concept-v2/<surface>/final/ layout.

2. The demo's Loom same-stem explainers are missing

The complete lookbook/briefs/03-loom/final/ tree contains only README.md, whose state table links seven individual Markdown files that are absent. A shared README does not satisfy the per-PNG same-stem explainer requirement.

At least the first two explainers can be recovered from already-reviewed product files, without inventing behavior:

• mockups/ui-concept-v2/03-loom/final/01-follow-loaded-tail.md
• mockups/ui-concept-v2/03-loom/final/02-temporal-replay.md

Check the current mirror for the remaining five before copying; audit all other final surfaces as part of export validation rather than assuming their README substitutes for individual briefs.

3. Moved briefs retain broken relative authority/image links

For example, lookbook/briefs/01-brain/final/01-registry-overview.md links ../../IMPLEMENTATION.md. In the split layout that resolves to lookbook/briefs/IMPLEMENTATION.md, not the existing lookbook/IMPLEMENTATION.md. The co-located image links in the demo's Loom final README are likewise not valid after separating PNGs and briefs.

Fix links according to the destination layout. Do not apply a global relative-path replacement to the product mirror, where its original traversal is appropriate.

4. Shared prose disagrees about two implementation-sensitive behaviors

• INTERACTION-STATES.md still describes Loom as time down and hosts across. The final Loom manifest, individual product briefs, and IMPLEMENTATION.md specify time left-to-right and hierarchical execution branches. Label the former as the current legacy baseline, and make the final-state interaction matrix unambiguous; do not let an implementer preserve the old geometry under the final-plate label.
• Brain 05 allows energy to traverse 'one or more relations', while DESIGN-SYSTEM.md, the Brain interaction matrix, and the inspected RegistryFieldView behavior constrain activity to one evidenced drawn hop, with sibling checkouts dark. Reconcile this wording explicitly. Preserve the existing one-hop behavior until a separate approved contract defines any expansion; this documentation repair does not authorize it.

Paused playback and following the loaded tail are not inherently contradictory: the existing playback state has playing:false with followLive:true. Do not introduce a spurious behavioral change while reconciling prose.

Smallest repair

1. Keep the accepted PNGs and their concept/synthetic labels unchanged. Restore missing same-stem briefs from verified current authority, preserving provenance and lifecycle rather than promoting archive files silently.
2. Repair demo gallery, per-surface README, and authority links for its pngs/ + briefs/ structure. Keep the product mirror's co-located layout working.
3. Use one small manifest/export validation step in the existing tooling: each current final PNG maps to exactly one same-stem explainer, every local link resolves within the intended pack, and all fourteen surface names/order match the canonical navigation. A split layout is acceptable if the mapping and links are explicit.
4. Record source commit and asset blob identities so an implementer can distinguish the same mirrored plate from a newer revision. Validate mirror content or documented transformations; do not demand identical bytes for layout-specific relative links.
5. Separate current implementation inventory from accepted target behavior in the shared interaction authority. Keep freshness, source grades, admission rules, and unavailable-state boundaries unchanged.

Acceptance

• Brain 01–05 and Loom 01–07 can each be opened from the demo gallery and navigated to a real same-stem brief and the correct shared authorities.
• Enumerating the final pack reports missing, orphaned, or duplicate mappings explicitly; the check fails on a deliberately missing brief or broken local link.
• The canonical rail remains Brain, Explorer, Loom, Sessions, Agents, Code, Knowledge, Delivery, Automations, Observatory, Costs, Settings, Work, Workflows.
• The repaired documents distinguish legacy vertical Loom from the accepted horizontal target and do not silently authorize multi-hop activity.
• No concept PNG is imported into the shipping dashboard, no fixture is relabelled as live evidence, and no source freshness threshold changes.
• Report which pack checks were actually executed. Run asset validation at the appropriate documentation/export boundary; do not add an image-processing dependency to ordinary Rust builds or a new general-purpose content platform.