fix(reporting): surface the coverage "no certificate" count on the strip

The confidence strip showed only the provenance "estimated" figure (824:
389), which counts expired-slot homes as modelled — so the #393 coverage
improvement (only 27 homes truly lack a certificate) wasn't visible on the
reporting page, only on data-quality.

Add the coverage count alongside it: getBaselineAggregates now also returns
noCertificate (withoutEpcSql — the tested classifyEpcEvidence "no-certificate"
case), threaded through BaselineMetrics; a new "no-certificate" drill filter
backs the strip item. The strip now reads e.g. "estimated 389 · no
certificate 27" — provenance and coverage side by side, per #393.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/api/portfolio/[portfolioId]/reporting/properties/route.ts

@@ -9,6 +9,7 @@ import {
   effectiveEpcBandSql,
   estimatedSql,
   isExpiredSql,
+  withoutEpcSql,
   likelyDowngradeSql,
   likelyUpgradeSql,
   provenanceSignalSql,
@@ -29,6 +30,7 @@ const FILTERS = [
   "band",
   "estimated",
   "expired",
+  "no-certificate",
   "likely-downgrade",
   "likely-upgrade",
   "measure",
@@ -84,6 +86,8 @@ export async function GET(
     // guard — an expired-slot home is estimated AND expired, and this drill must
     // match the Expired count (ADR-0014, PR #393). Twin: classifyEpcEvidence.
     expired: sql`${isExpiredSql(sql`e`)} = true`,
+    // Coverage: no certificate of any kind (the #393 "without an EPC" homes).
+    "no-certificate": sql`${withoutEpcSql(sql`e`)} = true`,
     "likely-downgrade": likelyDowngradeSql,
     "likely-upgrade": likelyUpgradeSql,
     measure: sql`EXISTS (

src/app/portfolio/[slug]/(portfolio)/reporting/ReportingClientArea.tsx

@@ -830,6 +830,13 @@ function ConfidenceStrip({
           onDrill({ filter: "estimated", title: "Estimated EPCs" })
         }
       />
+      <Item
+        label="no certificate"
+        value={baseline.noCertificate}
+        onClick={() =>
+          onDrill({ filter: "no-certificate", title: "Homes without a certificate" })
+        }
+      />
       <Item
         label="expired"
         value={baseline.expiredEpcs}

src/app/portfolio/[slug]/(portfolio)/reporting/components/DrillDownShelf.tsx

@@ -21,6 +21,7 @@ export interface DrillTarget {
     | "band"
     | "estimated"
     | "expired"
+    | "no-certificate"
     | "likely-downgrade"
     | "likely-upgrade"
     | "measure";

src/lib/reporting/server.ts

@@ -82,6 +82,7 @@ export async function getBaselineAggregates(
   lodgedNoCertificate: number;
   estimatedCounts: EstimatedCounts;
   expiredEpcs: number;
+  noCertificate: number;
 }> {
   const est = estimatedSql(sql`e`);
   const bandExpr = sql`COALESCE((${effectiveEpcBandSql})::text, 'Unknown')`;
@@ -133,6 +134,9 @@ export async function getBaselineAggregates(
       -- estimated AND expired, and the Expired count must include it (ADR-0014,
       -- PR #393). Twin: classifyEpcEvidence (@/lib/reporting/epcEvidence).
       SUM(CASE WHEN ${isExpiredSql(sql`e`)} = true THEN 1 ELSE 0 END)::int AS expired,
+      -- Coverage: no certificate of any kind (the #393 "without an EPC" figure),
+      -- distinct from the provenance estimated count above. Twin: classifyEpcEvidence.
+      SUM(CASE WHEN ${withoutEpcSql(sql`e`)} = true THEN 1 ELSE 0 END)::int AS no_certificate,
       ${bandCols},
       ${lodgedBandCols}
     FROM property p
@@ -189,6 +193,7 @@ export async function getBaselineAggregates(
       actual: Number(row.actual ?? 0),
     },
     expiredEpcs: Number(row.expired ?? 0),
+    noCertificate: Number(row.no_certificate ?? 0),
   };
 }
 
@@ -285,6 +290,7 @@ export async function loadBaselineMetrics(
     lodgedNoCertificate: aggregates.lodgedNoCertificate,
     estimatedCounts: aggregates.estimatedCounts,
     expiredEpcs: aggregates.expiredEpcs,
+    noCertificate: aggregates.noCertificate,
     likelyDowngrades,
   };
 }

src/lib/reporting/types.ts

@@ -54,6 +54,8 @@ export interface BaselineMetrics {
   lodgedNoCertificate: number;
   estimatedCounts: EstimatedCounts;
   expiredEpcs: number;
+  /** Coverage: homes with no certificate of any kind (the #393 "without an EPC" figure). */
+  noCertificate: number;
   likelyDowngrades: number;
 }