PR Review Summary

Status: Approved

🪜 Strategic-Fit Decision

Per §9 Strategic-Fit Step-Back:

• Decision: Approve
• Rationale: Minimal, correct, evidence-complete repair of a confirmed realization defect; the disclosed pre-existing failure is bracketed honestly (verified at two dev heads by this reviewer); no delivered-scope defect to send back. Approve+Follow-Up is unnecessary — the systematic guard was pre-split into #15965 by design, not deferred as debt.

Peer-Review Opening: Clean, minimal, and honestly bracketed — the RED→GREEN witness discipline on display here is the pattern for the whole overlay-geometry class. I reproduced the witness and the bracket at the exact head rather than quoting your prose; notes below.

🧭 Patch-Blind Premise Snapshot

• Inputs Read Before Patch: #15966 + the author's three A2A evidence messages (live measurement at 61a8d34e6d: indicator layer viewport-rooted y=0..720, tab-into preview −98px from target zone, top edge chip y=10..36 overlapping the tourbar); current dev Workspace.scss; the §06 coordinate contract in src/dashboard/DockDragAffordances.mjs:103-170; Demo-A's containing-block precedent; #15172 (host-relative edge-band precedent); my own take-16 footage (t38) showing the same displacement signature — I misread it there, so this premise came pre-falsified.
• Expected Solution Shape: CSS-only containing-block repair (host position: relative + overlay children absolute/inset), zero JS geometry changes, no px constants in JS; a RED→GREEN e2e witness proving layer equality + containment + chip exclusion + preview alignment, isolated from any pre-existing suite noise.
• Patch Verdict: Matches — the diff IS the expected shape (Workspace.scss: host relative + direct-child .neo-dock-preview inset:0 / pointer-events:none / z-index:25); the witness is a deliberately cancellation-only journey, decoupled from the pre-existing release-journey failure on dev.
• Premise Coherence: coheres: verify-before-assert — the PR exists because a live measurement falsified the realization against the documented §06 intent; friction→gold — the operator's visual catch became a mechanical guard within hours.

🕸️ Context & Graph Linking

• Target Epic / Issue ID: Resolves #15966
• Related Graph Nodes: #15965 (systematic rect layer, blocked-by this PR), #15955 (adjacent flicker taxonomy), #15172 (host-relative edge-band precedent), #13158 (docking polish umbrella), ADR 0029

🔬 Depth Floor

Challenge (non-blocking): the top-chip selector can return null — .neo-dashboard-dock-drop-chip-top:not(.neo-dashboard-dock-drop-indicator-off) misses whenever the hovered zone's candidate set carries no edge-top chip; readRect(null) returns null and intersects(null, tourbar) then throws an opaque TypeError instead of a named failure — and had it not crashed, a missing chip would have made the tourbar-exclusion assertion vacuous. Suggest an explicit existence gate before the exclusion assert (expect(geometry.topChip, 'top edge chip painted').toBeTruthy()) so the regression's precondition is itself guarded. Author's call — in the current scenario the chip renders and the assertion bites. Second, smaller: the new assertions read class selectors via page.evaluate — right for a fix-critical witness; #15965's systematic layer will port the families to component-id getDomRect for restyle-proofing, so no change requested here.

Rhetorical-Drift Audit (per guide §7.4):

• PR description: framing matches what the diff substantiates (no overshoot)
• Anchor & Echo summaries: precise codebase terminology, no metaphor or source-code snapshot anchor that overshoots durable intent
• [RETROSPECTIVE] tag: accurately characterizes what shipped (no inflation of architectural significance)
• Linked anchors: cited tickets/PRs actually establish the claimed pattern (no borrowed authority)

Findings: Pass — "fills that host below the indicator menu without owning pointer input" and "no longer renders from viewport top: 0" are mechanically exact; the Deltas-from-ticket section honestly names the journey isolation.

🧠 Graph Ingestion Notes

• [KB_GAP]: none — the author demonstrated correct command of the containing-block/offsetParent contract.
• [TOOLING_GAP]: e2e Neural Link journeys do not run in CI — a dev-side e2e regression (the release-commit journey, below) can persist invisible to every gate. Not this PR's scope; named for the record and filed separately by this reviewer as #15968.
• [RETROSPECTIVE]: The defect shipped through a green suite because geometry was never asserted. The enduring value pair here is the witness discipline: the author proved the new assertions RED before the repair (position: static) and GREEN after, at the exact head — the pattern for the whole overlay-geometry class.

🎯 Close-Target Audit

• Close-targets identified: Resolves #15966 (newline-isolated, valid leaf, not epic-labeled); Related: #15965 non-closing.

Findings: Pass

🪜 Evidence Audit

• PR body contains an Evidence: declaration line
• Achieved evidence ≥ close-target required evidence, OR residuals are explicitly listed
• If residuals exist: close-target issue body has the residuals annotated
• Two-ceiling distinction: PR body distinguishes sandbox ceiling from author didn't probe further
• Evidence-class collapse check: review language does NOT promote L1/L2 evidence to L3/L4 framing
• Deployment causality: any external/runtime receipt used as a merge gate is reachable from this exact unmerged head; otherwise Post-Merge Validation

Findings: Pass — Evidence: L3 (real Chrome pointer gesture + Neural Link worker truth + browser-painted rect assertions) → L3 required. No residuals. matches the observable-geometry ACs; this reviewer independently reproduced the L3 receipt at the exact head (below).

N/A Audits — 📑 📡 🔗 🛂 📜 🔌 🧠

N/A across listed dimensions: internal styling + e2e spec only — no public/consumed API surface (no Contract Ledger owed), no OpenAPI surface, no cross-substrate convention introduced, no new architectural abstraction, no authority-cited demands, no wire-format/schema change, no turn-memory-scope file.

🧪 Test-Evidence & Location Audit

• Execution evidence: exact-head required CI green at d6cbe62aec (lint ×2, lint-pr-body, lint-pr-review-body, CodeQL, components, integration-unified, unit) + author non-CI receipt (RED→GREEN witness) present and current-head-appropriate.
• Reviewer falsifier (two, both reproduced): (1) full WorkstationDragAffordancesNL spec at exact head d6cbe62aec → new geometry journey + design-language journey GREEN, release-commit journey fails exactly as disclosed; (2) the SAME release-commit journey on plain dev 32cd74a370 AND f33eb328c2 → identical failure — the bracket "pre-existing, not from this patch" is verified honest at two independent dev heads (filed as #15968).
• Test location: the new journey lives in the owning spec — canonical placement per the unit-test skill.

Findings: Pass

📋 Required Actions

No required actions — eligible for human merge.

Follow-up notes (non-blocking, author's call): the topChip existence gate above. Separately: the dev-side release-journey regression reproduced at two dev heads is filed as #15968 — it predates this PR by construction.

📊 Evaluation Metrics

• [ARCH_ALIGNMENT]: 100 — checked and cleared: zero JS geometry changes (the §06 controller math was already host-local; the boundary held), zero px constants added to JS, the repair lands in the owning skin (resources/scss/src/apps/workstation/Workspace.scss) matching Demo-A's app-side precedent, pointer-ownership single-sourced to the sort-zone drag.
• [CONTENT_COMPLETENESS]: 100 — checked and cleared: helper JSDoc present (readParkedOverlayGeometry documented with summary + params + returns), PR body carries Deltas-from-ticket disclosure, an Evidence line, and honest partial-suite accounting — the three sections that usually go missing.
• [EXECUTION_QUALITY]: 97 — witness reproduced GREEN at exact head; assertions cover the four fix-critical families (layer equality, containment, chip exclusion, ≤1px alignment) with worker-truth-first ordering. −3: the null-chip selector edge named in Depth Floor — an opaque TypeError instead of a named failure when the precondition lapses.
• [PRODUCTIVITY]: 100 — #15966's acceptance surface fully delivered with receipts; the split boundary with #15965 respected exactly.
• [IMPACT]: 82 — repairs an operator-visible flagship defect and establishes the assertion seam #15965 systematizes; bounded blast radius (one skin + one spec).
• [COMPLEXITY]: 25 — two files, ~110 added lines, one CSS concept + one e2e journey; low reader load.
• [EFFORT_PROFILE]: Quick Win — operator-visible repair plus a regression guard at low complexity.

Closing: merge-safe at green CI. The bracketed dev-side release-journey failure is real and reproduced — it lives in #15968 now and predates this PR by construction.