feat(identity): count email clicks as daily aggregates

layers/admin/server/api/admin/weekly.get.ts

@@ -25,7 +25,9 @@ interface WindowRow {
   trending_rows: number
   first_claimed_at: number
   last_sent_at: number | null
+  clicks: number
   unsubscribes: number
+  share_clicks: number
 }
 
 interface ProblemRow {
@@ -56,8 +58,12 @@ export interface AdminWeeklyResponse {
     trendingRows: number
     firstClaimedAt: number
     lastAcceptedAt: number | null
+    /** Aggregate link clicks for this issue, share links excluded. */
+    clicks: number
+    clicksPerAccepted: number | null
     unsubscribes: number
     unsubscribeRate: number | null
+    shareClicks: number
   }>
   /** Rows without a resolved provider outcome, newest first. */
   problems: Array<{
@@ -94,6 +100,11 @@ export default defineApiHandler({
                 SUM(trending_count) AS trending_rows,
                 MIN(claimed_at) AS first_claimed_at,
                 MAX(r.sent_at) AS last_sent_at,
+                (SELECT COALESCE(SUM(c.clicks), 0)
+                 FROM email_click_counts c
+                 WHERE c.campaign = 'weekly'
+                   AND c.issue = r.window_end
+                   AND c.placement != 'share') AS clicks,
                 (SELECT COUNT(DISTINCT e.user_id)
                  FROM email_preference_events e
                  WHERE e.list = 'weekly'
@@ -105,7 +116,12 @@ export default defineApiHandler({
                        AND er.sent_at IS NOT NULL
                        AND e.occurred_at >= er.sent_at
                        AND e.occurred_at < er.sent_at + 604800
-                   )) AS unsubscribes
+                   )) AS unsubscribes,
+                (SELECT COALESCE(SUM(c.clicks), 0)
+                 FROM email_click_counts c
+                 WHERE c.campaign = 'weekly'
+                   AND c.issue = r.window_end
+                   AND c.placement = 'share') AS share_clicks
          FROM weekly_runs r
          GROUP BY r.window_end
          ORDER BY r.window_end DESC

layers/admin/server/utils/weekly-engagement.ts

@@ -1,18 +1,36 @@
 export interface WeeklyEngagementCounts {
   accepted: number
+  /** Counted clicks on the issue's links, share links excluded. */
+  clicks: number
   unsubscribes: number
+  /** Counted clicks on the share link. */
+  share_clicks: number
 }
 
 export interface WeeklyEngagementSummary {
+  clicks: number
+  /**
+   * Clicks per accepted email. Counts are aggregate, so one reader can click
+   * twice; this is not a unique click rate.
+   */
+  clicksPerAccepted: number | null
   unsubscribes: number
   unsubscribeRate: number | null
+  shareClicks: number
+}
+
+function perAccepted(count: number, accepted: number): number | null {
+  return accepted > 0 ? count / accepted : null
 }
 
 export function summarizeWeeklyEngagement(
   counts: WeeklyEngagementCounts,
 ): WeeklyEngagementSummary {
   return {
+    clicks: counts.clicks,
+    clicksPerAccepted: perAccepted(counts.clicks, counts.accepted),
     unsubscribes: counts.unsubscribes,
-    unsubscribeRate: counts.accepted > 0 ? counts.unsubscribes / counts.accepted : null,
+    unsubscribeRate: perAccepted(counts.unsubscribes, counts.accepted),
+    shareClicks: counts.share_clicks,
   }
 }

layers/identity/server/api/e/[campaign].get.ts

@@ -0,0 +1,39 @@
+import { getQuery, getRouterParam, sendRedirect, setHeader } from 'h3'
+import { defineApiHandler } from '#shared/server/handler'
+import { parseEmailClick, recordEmailClick } from '../../utils/email-clicks'
+
+/**
+ * Counts a click from the weekly or digest email, then sends the reader on.
+ *
+ * Only the aggregate counter changes. The link names no reader, and nothing
+ * from the request is stored beyond the campaign, issue, placement, and path.
+ * The wide event carries the campaign and placement, never the path.
+ *
+ * Counting is best effort. A reader who clicked is owed the page, so a failed
+ * write is reported and the redirect still happens.
+ */
+export default defineApiHandler({
+  handler: async ({ event, platform }) => {
+    const click = parseEmailClick(getRouterParam(event, 'campaign'), getQuery(event))
+
+    if (click._tag === 'counted') {
+      const { campaign, placement } = click.key
+      await recordEmailClick(platform.db, click.key, new Date()).then(
+        () => emitOperationalEvent(createWideEvent({ operation: 'email-click', outcome: 'success', reason: `${campaign}/${placement}` }), 'info'),
+        (error: unknown) => emitOperationalEvent(createWideEvent({
+          operation: 'email-click',
+          outcome: 'failed',
+          reason: `${campaign}/${placement}: ${error instanceof Error ? error.name : 'unknown'}`,
+        })),
+      )
+    }
+    else {
+      emitOperationalEvent(createWideEvent({ operation: 'email-click', outcome: 'skipped', reason: click.reason }), 'info')
+    }
+
+    // A click is a one-off, and a cached redirect would hide every later one.
+    setHeader(event, 'cache-control', 'private, no-store')
+    // An invalid target names no page. Home is the safe landing.
+    return sendRedirect(event, click._tag === 'invalid' ? '/' : click.to, 302)
+  },
+})

layers/identity/server/utils/daily-health-check.spec.ts

@@ -44,6 +44,7 @@ function summary(overrides: Partial<DailyHealthCheckSummary> = {}): DailyHealthC
       newUsers24h: 1,
       digestsSent24h: 4,
       digestsFailed24h: 0,
+      emailClicks: { fromDay: '2026-07-21', weekly: 2, digest: 5 },
     },
     pipeline: {
       syncJobs: [{ name: 'sync-github-skills', status: 'ok', lastRunAt: 1_774_473_600, stale: false, error: null }],
@@ -332,6 +333,7 @@ describe('buildDailyHealthCheck', () => {
       CREATE TABLE skill_subscriptions (owner TEXT, repo TEXT);
       CREATE TABLE collection_skills_v2 (owner TEXT, repo TEXT);
       CREATE TABLE activity (owner TEXT, repo TEXT, name TEXT, occurred_at INTEGER);
+      CREATE TABLE email_click_counts (day TEXT, campaign TEXT, issue INTEGER, placement TEXT, path TEXT, clicks INTEGER);
       CREATE TABLE digest_runs (
         status TEXT,
         sent_at INTEGER,
@@ -399,6 +401,11 @@ describe('buildDailyHealthCheck', () => {
       INSERT INTO collections_v2 VALUES (NULL);
       INSERT INTO user_starred_repos VALUES ('owner', 'repo');
       INSERT INTO activity VALUES ('owner', 'repo', 'skill', ${nowSec - 60});
+      -- Counters are per UTC day. The window starts on 07-21, so 07-20 is out.
+      INSERT INTO email_click_counts VALUES ('2026-07-20', 'digest', 1, 'overflow', '/me/likes', 40);
+      INSERT INTO email_click_counts VALUES ('2026-07-21', 'digest', 1, 'overflow', '/me/likes', 2);
+      INSERT INTO email_click_counts VALUES ('2026-07-22', 'digest', 1, 'footer', '/', 3);
+      INSERT INTO email_click_counts VALUES ('2026-07-22', 'weekly', 2, 'cta', '/skills', 1);
       INSERT INTO digest_runs VALUES ('sent', ${nowSec - 60}, ${nowSec - 60}, ${nowSec - 60}, ${nowSec - 60});
       -- The discovery cursor is a single fixed row in production, and the
       -- health query reads it by key. Without it the query returns no row at
@@ -470,6 +477,7 @@ describe('buildDailyHealthCheck', () => {
     expect(built.warnings).toEqual([])
     expect(built.inventory).toMatchObject({ skills: 1, repos: 2, users: 1, watchedRepos: 1 })
     expect(built.activity).toMatchObject({ newSkills24h: 1, repoChanges24h: 1, digestsSent24h: 1 })
+    expect(built.activity.emailClicks).toEqual({ fromDay: '2026-07-21', weekly: 1, digest: 5 })
     expect(built.pipeline).toMatchObject({
       newlyBrokenReposTotal24h: 1,
       newlyBrokenReposImpacted24h: 0,

layers/identity/server/utils/daily-health-check.ts

@@ -66,6 +66,18 @@ export interface DailyHealthCheckSummary {
     newUsers24h: number
     digestsSent24h: number
     digestsFailed24h: number
+    /**
+     * Aggregate email link clicks, per campaign.
+     *
+     * Counters are kept per UTC day, so this sums whole days from `fromDay`
+     * onwards rather than an exact 24 hours. Digest clicks are the Loop 2
+     * evidence bar.
+     */
+    emailClicks: {
+      fromDay: string
+      weekly: number
+      digest: number
+    }
     /**
      * The most recent weekly run, not a 24 hour count.
      *
@@ -783,6 +795,17 @@ async function loadInventory(db: D1Database): Promise<DailyHealthCheckSummary['i
   }
 }
 
+async function loadEmailClicks(db: D1Database, fromDay: string): Promise<DailyHealthCheckSummary['activity']['emailClicks']> {
+  const row = await first<{ weekly: number | null, digest: number | null }>(db, `
+    SELECT
+      SUM(clicks) FILTER (WHERE campaign = 'weekly') AS weekly,
+      SUM(clicks) FILTER (WHERE campaign = 'digest') AS digest
+    FROM email_click_counts
+    WHERE day >= ?1
+  `, [fromDay])
+  return { fromDay, weekly: numberValue(row.weekly), digest: numberValue(row.digest) }
+}
+
 async function loadActivity(
   db: D1Database,
   sinceSec: number,
@@ -799,13 +822,16 @@ async function loadActivity(
        + (SELECT COUNT(*) FROM digest_runs
           WHERE status IN ('sending', 'uncertain'))) AS digests_failed_24h
   `, [sinceSec])
+  const fromDay = new Date(sinceSec * 1000).toISOString().slice(0, 10)
+  const emailClicks = await capture(warnings, 'email clicks', { fromDay, weekly: 0, digest: 0 }, () => loadEmailClicks(db, fromDay))
   const weekly = await capture(warnings, 'weekly delivery', null, () => loadWeeklyRun(db))
   return {
     newSkills24h: numberValue(row.new_skills_24h),
     repoChanges24h: numberValue(row.repo_changes_24h),
     newUsers24h: numberValue(row.new_users_24h),
     digestsSent24h: numberValue(row.digests_sent_24h),
     digestsFailed24h: numberValue(row.digests_failed_24h),
+    emailClicks,
     weekly,
   }
 }
@@ -1153,6 +1179,7 @@ export async function buildDailyHealthCheck(
     newUsers24h: 0,
     digestsSent24h: 0,
     digestsFailed24h: 0,
+    emailClicks: { fromDay: since.toISOString().slice(0, 10), weekly: 0, digest: 0 },
     weekly: null,
   }, () => loadActivity(db, sinceSec, warnings))
   const pipeline = await capture(warnings, 'pipeline', {

layers/identity/server/utils/digest-delivery.ts

@@ -615,6 +615,7 @@ export async function runDigestDeliveryForUser(
   const rendered = deps.render({
     login: user.login,
     recipientName: user.name ?? null,
+    countClicks: true,
     windowStart: selection.windowStart,
     windowEnd: selection.windowEnd,
     unsubscribeUrl,

layers/identity/server/utils/digest-template.ts

@@ -21,6 +21,8 @@ export interface DigestRepoEntry {
 export interface DigestRenderInput {
   login: string
   recipientName?: string | null
+  /** Route same-site links through the aggregate click counter. Real sends only. */
+  countClicks?: boolean
   windowStart: number
   windowEnd: number
   entries: DigestRepoEntry[]
@@ -56,6 +58,7 @@ export function renderDigest(input: DigestRenderInput): DigestRender {
   return renderWeekly({
     edition: 'digest',
     recipientName: input.recipientName ?? null,
+    countClicks: input.countClicks ?? false,
     windowStart: input.windowStart,
     windowEnd: input.windowEnd,
     likedChanges,