Polish change detection density

CHANGELOG.md

@@ -7,6 +7,14 @@
 
 # Changelog
 
+## Sprint 87 Change Detection density polish (2026-06-20)
+
+- Grouped Change Detection heading, input controls, result states, summary and warnings into focused surfaces.
+- Reused shared result-state cards for not-enough-data and error states.
+- Added compact desktop/mobile grids for vector inputs and change summary metrics.
+- Added static regression coverage for Change Detection hierarchy and density contracts.
+- No API contracts, migrations, backend behavior, provider fetching or AI model behavior changed.
+
 ## Sprint 86 QA/QC workspace density polish (2026-06-20)
 
 - Grouped QA/QC summary, dataset evidence, refresh/filter controls and result history into focused surfaces.

backend/tests/test_sprint87_change_detection_density.py

@@ -0,0 +1,53 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[2]
+
+
+def test_change_detection_panel_exposes_structured_surfaces() -> None:
+    panel = (ROOT / "frontend" / "src" / "components" / "analysis" / "ChangeDetectionPanel.tsx").read_text(
+        encoding="utf-8"
+    )
+
+    assert 'className="panel change-detection-shell"' in panel
+    assert 'className="panel-header change-detection-heading"' in panel
+    assert 'className="change-detection-input-surface"' in panel
+    assert 'aria-label="Change detection input controls"' in panel
+    assert 'className="change-detection-state-stack"' in panel
+    assert 'className="change-detection-result-surface"' in panel
+    assert 'aria-label="Change detection result summary"' in panel
+    assert 'className="change-detection-warning-surface"' in panel
+
+
+def test_change_detection_panel_preserves_existing_compare_controls() -> None:
+    panel = (ROOT / "frontend" / "src" / "components" / "analysis" / "ChangeDetectionPanel.tsx").read_text(
+        encoding="utf-8"
+    )
+
+    assert "onSourceDatasetChange" in panel
+    assert "onTargetDatasetChange" in panel
+    assert "onIouThresholdChange" in panel
+    assert "onIncludeUnchangedChange" in panel
+    assert "onRun" in panel
+    assert "Compare vectors" in panel
+    assert "Upload at least two vector datasets to compare." in panel
+    assert "result.added_count" in panel
+    assert "result.removed_count" in panel
+    assert "result.unchanged_count" in panel
+
+
+def test_change_detection_density_css_contracts() -> None:
+    css = (ROOT / "frontend" / "src" / "styles" / "app.css").read_text(encoding="utf-8")
+
+    assert ".change-detection-shell" in css
+    assert ".change-detection-heading" in css
+    assert ".change-detection-input-surface" in css
+    assert ".change-detection-state-stack" in css
+    assert ".change-detection-result-surface" in css
+    assert ".change-detection-warning-surface" in css
+    assert ".change-detection-shell .form-grid" in css
+    assert ".change-detection-shell .summary-grid" in css
+    assert "grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));" in css
+    assert "grid-template-columns: repeat(auto-fit, minmax(7.5rem, 1fr));" in css

docs/CODEX_EXECUTION_LOG.md

@@ -3143,3 +3143,31 @@ Limitations:
 
 Next recommended pass:
 - Continue with Change Detection panel hierarchy and analysis workspace balance after this pass is deployed and visually checked.
+
+## Sprint 87 Change Detection density polish (2026-06-20)
+
+Changed:
+- Wrapped Change Detection input controls in `change-detection-input-surface`.
+- Replaced loose error/empty text with shared `result-state` cards inside `change-detection-state-stack`.
+- Wrapped result metrics in `change-detection-result-surface`.
+- Wrapped warning output in `change-detection-warning-surface`.
+- Added compact responsive CSS contracts for Change Detection form and summary grids.
+- Added `backend/tests/test_sprint87_change_detection_density.py`.
+- Updated `frontend/README.md`, `docs/TODO.md` and `CHANGELOG.md`.
+
+Tested:
+- Live browser pre-check attempt against `http://192.168.10.150:1202` hit a transient browser automation click timeout on the QA/QC workspace nav; source review showed Change Detection was still the older header/form/summary stack.
+- Red step: `python -m pytest backend/tests/test_sprint87_change_detection_density.py -q` failed on missing Change Detection surface and density CSS contracts.
+- `python -m pytest backend/tests/test_sprint87_change_detection_density.py backend/tests/test_sprint18_change_detection.py backend/tests/test_sprint39_frontend_orchestration_hooks.py backend/tests/test_sprint86_quality_workspace_density.py backend/tests/test_sprint47_workbench_interaction_smoke.py -q` (`20 passed`)
+- `cd frontend && npm run typecheck`
+- `cd frontend && npm run build`
+- Full readiness and Tower deploy pending in this pass.
+
+Open:
+- None known before full readiness/deploy validation.
+
+Limitations:
+- Frontend Change Detection presentation hierarchy only; no change-detection behavior, API contract, persistence, migration, provider fetching or AI/model changes.
+
+Next recommended pass:
+- Continue with AI Labs run-form hierarchy and detection/segmentation result density after this pass is deployed and visually checked.

docs/TODO.md

@@ -76,6 +76,7 @@ This file now starts with the current implementation status. Older preparation/b
 - [x] Add Data workspace selected-summary and panel density polish.
 - [x] Add Map workspace panel hierarchy and layer-control density polish.
 - [x] Add QA/QC workspace result hierarchy and filter density polish.
+- [x] Add Change Detection panel hierarchy and analysis workspace density polish.
 
 ## Sprint 8 status
 

frontend/README.md

@@ -10,6 +10,8 @@ Map workspace now surfaces the selected AOI, active layer and rendered feature s
 
 QA/QC Results now separates persisted check summary, candidate/reference evidence, refresh/filter controls and result history into focused surfaces. Existing filters, refresh behavior, metric cards and stored result rendering are unchanged, with denser mobile grids for the same controls.
 
+Change Detection now follows the same analysis workspace hierarchy: vector input controls, error/empty states, result metrics and warnings are separated into focused surfaces while the existing compare action and map overlay result flow remain unchanged.
+
 AI Labs uses the same mobile-density baseline for Detection and Segmentation model cards, run forms, QA/result summaries and scroll-safe result tables. This keeps long model ids, tile paths and artifact paths from widening the workbench on phones.
 
 Exports and System provider capabilities now use compact, mobile-safe cards for handoff actions, artifact filters and provider metadata. Long provider limitations, export ids and artifact paths wrap inside their cards instead of widening the workbench.

frontend/src/components/analysis/ChangeDetectionPanel.tsx

@@ -37,8 +37,8 @@ export function ChangeDetectionPanel({
   onRun,
 }: ChangeDetectionPanelProps): JSX.Element {
   return (
-    <section className="panel">
+    <section className="panel change-detection-shell">
-      <div className="panel-header">
+      <div className="panel-header change-detection-heading">
         <div>
           <p className="eyebrow">Analysis</p>
           <h2>Change Detection</h2>
@@ -48,6 +48,7 @@ export function ChangeDetectionPanel({
         </button>
       </div>
 
+      <div className="change-detection-input-surface" aria-label="Change detection input controls">
         <div className="form-grid">
           <label>
             Source vector
@@ -91,11 +92,25 @@ export function ChangeDetectionPanel({
             Include unchanged geometry
           </label>
         </div>
+      </div>
 
-      {error ? <p className="error">{error}</p> : null}
+      <div className="change-detection-state-stack">
-      {!error && vectorDatasets.length < 2 ? <p className="muted">Upload at least two vector datasets to compare.</p> : null}
+        {error ? (
+          <div className="result-state result-state-error">
+            <strong>Change detection failed.</strong>
+            <p>{error}</p>
+          </div>
+        ) : null}
+        {!error && vectorDatasets.length < 2 ? (
+          <div className="result-state result-state-empty">
+            <strong>Not enough vector datasets</strong>
+            <p>Upload at least two vector datasets to compare.</p>
+          </div>
+        ) : null}
+      </div>
 
       {result ? (
+        <div className="change-detection-result-surface" aria-label="Change detection result summary">
           <div className="summary-grid">
             <div>
               <span className="metric">{result.added_count}</span>
@@ -114,14 +129,18 @@ export function ChangeDetectionPanel({
               <span>Map features</span>
             </div>
           </div>
+        </div>
       ) : null}
 
       {result?.warnings.length ? (
+        <div className="change-detection-warning-surface">
+          <strong>Warnings</strong>
           <ul className="compact-list">
             {result.warnings.map((warning) => (
               <li key={warning}>{warning}</li>
             ))}
           </ul>
+        </div>
       ) : null}
     </section>
   )

frontend/src/styles/app.css

@@ -1465,6 +1465,71 @@ button.entity-card {
   margin: 0;
 }
 
+.change-detection-shell {
+  display: grid;
+  gap: 0.75rem;
+}
+
+.change-detection-heading {
+  margin-bottom: 0;
+}
+
+.change-detection-input-surface,
+.change-detection-result-surface,
+.change-detection-warning-surface {
+  min-width: 0;
+  border: 1px solid var(--line);
+  border-radius: 8px;
+  padding: 0.72rem;
+  background: #ffffff;
+}
+
+.change-detection-input-surface {
+  background: linear-gradient(180deg, #ffffff, #f7fbf8);
+}
+
+.change-detection-state-stack {
+  display: grid;
+  gap: 0.55rem;
+}
+
+.change-detection-shell .form-grid {
+  grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
+  gap: 0.62rem;
+  margin: 0;
+}
+
+.change-detection-shell .form-grid label {
+  min-width: 0;
+}
+
+.change-detection-shell .form-grid input,
+.change-detection-shell .form-grid select {
+  width: 100%;
+  min-width: 0;
+}
+
+.change-detection-shell .summary-grid {
+  grid-template-columns: repeat(auto-fit, minmax(7.5rem, 1fr));
+  gap: 0.55rem;
+  margin: 0;
+}
+
+.change-detection-warning-surface {
+  border-color: rgba(180, 83, 9, 0.24);
+  background: rgba(180, 83, 9, 0.08);
+}
+
+.change-detection-warning-surface strong {
+  display: block;
+  color: #92400e;
+  font-size: 0.88rem;
+}
+
+.change-detection-warning-surface .compact-list {
+  margin-top: 0.45rem;
+}
+
 .quality-results-shell .quality-summary-grid {
   display: grid;
   grid-template-columns: repeat(3, minmax(0, 1fr));
@@ -2798,12 +2863,16 @@ button.entity-card {
   .quality-summary-surface,
   .quality-evidence-surface,
   .quality-control-surface,
-  .quality-history-surface {
+  .quality-history-surface,
+  .change-detection-input-surface,
+  .change-detection-result-surface,
+  .change-detection-warning-surface {
     padding: 0.58rem;
   }
 
   .quality-results-shell .quality-summary-grid,
-  .quality-results-shell .quality-history-controls {
+  .quality-results-shell .quality-history-controls,
+  .change-detection-shell .form-grid {
     grid-template-columns: repeat(auto-fit, minmax(8.25rem, 1fr));
     gap: 0.5rem;
   }
@@ -2811,7 +2880,8 @@ button.entity-card {
   .quality-results-shell .quality-handoff-grid,
   .quality-results-shell .quality-score-row,
   .quality-results-shell .quality-metric-grid,
-  .quality-results-shell .metric-list {
+  .quality-results-shell .metric-list,
+  .change-detection-shell .summary-grid {
     grid-template-columns: repeat(auto-fit, minmax(7.5rem, 1fr));
     gap: 0.5rem;
   }