feat: add shared team dashboard, regression alerts, weekly digest edge functions

Dashboard: Supabase edge function serving self-contained HTML with
PKCE OAuth, 6 parallel client-side REST queries, SVG charts, dark
theme, auto-refresh, who's-online from heartbeats. Public URL.

Regression alert: webhook on eval_runs INSERT, 5-min cooldown dedup
via alert_cooldowns, Slack notification on >5% pass rate drop.

Weekly digest: pg_cron Monday 9am UTC, aggregates 7-day team data,
Slack message with evals/ships/sessions/costs. 15 tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

supabase/functions/regression-alert/index.ts

@@ -0,0 +1,171 @@
+/**
+ * Regression alert edge function.
+ *
+ * Trigger: Database webhook on eval_runs INSERT.
+ * Logic: Compare new run's pass rate against recent baseline.
+ *        If >5% drop, POST to team's Slack webhook.
+ *        Dedup via alert_cooldowns table (5-min window).
+ *
+ * Uses service_role key (bypasses RLS) — standard for webhooks.
+ */
+
+import { createClient } from 'https://esm.sh/@supabase/supabase-js@2';
+
+interface WebhookPayload {
+  type: 'INSERT';
+  table: string;
+  record: {
+    id: string;
+    team_id: string;
+    repo_slug: string;
+    branch: string;
+    passed: number;
+    total_tests: number;
+    timestamp: string;
+  };
+  schema: string;
+}
+
+// --- Pure functions (testable) ---
+
+export function computePassRate(passed: number, total: number): number | null {
+  return total > 0 ? (passed / total) * 100 : null;
+}
+
+export function shouldAlert(
+  currentRate: number | null,
+  baselineRate: number | null,
+  thresholdPct: number = 5,
+): boolean {
+  if (currentRate === null || baselineRate === null) return false;
+  return baselineRate - currentRate > thresholdPct;
+}
+
+export function formatSlackMessage(opts: {
+  repoSlug: string;
+  branch: string;
+  previousRate: number;
+  currentRate: number;
+}): string {
+  const delta = opts.currentRate - opts.previousRate;
+  const arrow = delta < 0 ? 'regressed' : 'improved';
+  return [
+    `:warning: *Eval ${arrow}* on \`${opts.branch}\` (${opts.repoSlug})`,
+    `Pass rate: ${opts.previousRate.toFixed(0)}% → ${opts.currentRate.toFixed(0)}% (${delta > 0 ? '+' : ''}${delta.toFixed(0)}%)`,
+  ].join('\n');
+}
+
+// --- Main handler ---
+
+Deno.serve(async (req: Request) => {
+  try {
+    const payload: WebhookPayload = await req.json();
+    const { record } = payload;
+
+    if (!record || !record.team_id || !record.total_tests) {
+      return new Response('OK (skipped: missing fields)', { status: 200 });
+    }
+
+    const currentRate = computePassRate(record.passed, record.total_tests);
+    if (currentRate === null) {
+      return new Response('OK (skipped: total_tests=0)', { status: 200 });
+    }
+
+    const supabaseUrl = Deno.env.get('SUPABASE_URL')!;
+    const serviceKey = Deno.env.get('SUPABASE_SERVICE_ROLE_KEY')!;
+    const supabase = createClient(supabaseUrl, serviceKey);
+
+    // Check cooldown (5-min dedup)
+    const { data: cooldown } = await supabase
+      .from('alert_cooldowns')
+      .select('last_sent_at')
+      .eq('team_id', record.team_id)
+      .eq('repo_slug', record.repo_slug)
+      .eq('alert_type', 'regression')
+      .single();
+
+    if (cooldown?.last_sent_at) {
+      const cooldownMs = Date.now() - new Date(cooldown.last_sent_at).getTime();
+      if (cooldownMs < 5 * 60 * 1000) {
+        return new Response('OK (cooldown active)', { status: 200 });
+      }
+    }
+
+    // Get previous runs for baseline
+    const { data: previousRuns } = await supabase
+      .from('eval_runs')
+      .select('passed, total_tests')
+      .eq('team_id', record.team_id)
+      .eq('repo_slug', record.repo_slug)
+      .neq('id', record.id)
+      .order('timestamp', { ascending: false })
+      .limit(19);
+
+    if (!previousRuns || previousRuns.length < 2) {
+      return new Response('OK (not enough history)', { status: 200 });
+    }
+
+    // Compute baseline pass rate
+    const rates = previousRuns
+      .map(r => computePassRate(r.passed, r.total_tests))
+      .filter((r): r is number => r !== null);
+
+    if (rates.length === 0) {
+      return new Response('OK (no valid baseline)', { status: 200 });
+    }
+
+    const baselineRate = rates.reduce((a, b) => a + b, 0) / rates.length;
+
+    if (!shouldAlert(currentRate, baselineRate)) {
+      return new Response('OK (no regression)', { status: 200 });
+    }
+
+    // Get Slack webhook URL
+    const { data: setting } = await supabase
+      .from('team_settings')
+      .select('value')
+      .eq('team_id', record.team_id)
+      .eq('key', 'slack-webhook')
+      .single();
+
+    if (!setting?.value) {
+      console.log(`Regression detected but no Slack webhook configured for team ${record.team_id}`);
+      return new Response('OK (no webhook configured)', { status: 200 });
+    }
+
+    // Send Slack alert
+    const message = formatSlackMessage({
+      repoSlug: record.repo_slug,
+      branch: record.branch,
+      previousRate: baselineRate,
+      currentRate,
+    });
+
+    const slackRes = await fetch(setting.value, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ text: message }),
+    });
+
+    if (!slackRes.ok) {
+      console.error(`Slack webhook failed: ${slackRes.status} ${await slackRes.text()}`);
+    }
+
+    // Update cooldown
+    await supabase
+      .from('alert_cooldowns')
+      .upsert({
+        team_id: record.team_id,
+        repo_slug: record.repo_slug,
+        alert_type: 'regression',
+        last_sent_at: new Date().toISOString(),
+      });
+
+    console.log(`Regression alert sent: ${record.repo_slug} ${baselineRate.toFixed(0)}% → ${currentRate.toFixed(0)}%`);
+
+    return new Response('OK (alert sent)', { status: 200 });
+  } catch (err) {
+    console.error(`Regression alert error: ${err}`);
+    return new Response('OK (error logged)', { status: 200 });
+  }
+});