fix(stats): count only revenue-less users as connection burn

Burn incremented for every matured user who was not currently net-active,
which wrongly booked users who paid and later churned as connect-and-leave
leak (and mislabelled it 'never converted'). Restrict burn to users who never
earned net revenue: no subscription at all, or paid then refunded. A paid-then-
canceled user converted, so their connection cost is no longer burn.

app/Console/Commands/SendExperimentFunnelReportCommand.php

@@ -127,7 +127,7 @@ class SendExperimentFunnelReportCommand extends Command
                 [
                     'name' => 'Legend',
                     'value' => sprintf(
-                        'Assg = signups · Actd = activated (connected a bank or enabled AI = cost triggered) · Card = completed checkout (card on file) · MatU = matured assigned (cohort old enough to score for this variant) · Paid = live non-refunded subs among MatU · Conv%% = Paid ÷ MatU (net conversion, always ≤100%%, comparable across variants) · ARPU = MRR ÷ MatU (revenue per matured user) · MRR = monthly run-rate of paid subs (yearly ÷ 12) · Cost = est. connection cost of MatU (%s/connection) · Burn = connection cost of matured users not currently paying · CM = MRR − Cost · `pend`/`—` = no matured data yet.',
+                        'Assg = signups · Actd = activated (connected a bank or enabled AI = cost triggered) · Card = completed checkout (card on file) · MatU = matured assigned (cohort old enough to score for this variant) · Paid = live non-refunded subs among MatU · Conv%% = Paid ÷ MatU (net conversion, always ≤100%%, comparable across variants) · ARPU = MRR ÷ MatU (revenue per matured user) · MRR = monthly run-rate of paid subs (yearly ÷ 12) · Cost = est. connection cost of MatU (%s/connection) · Burn = connection cost of matured users who never earned net revenue (connected a bank but never paid, or paid then refunded) · CM = MRR − Cost · `pend`/`—` = no matured data yet.',
                         $this->money($report['costPerConnectionCents'], $report['currency']),
                     ),
                     'inline' => false,

app/Services/Stats/ExperimentFunnelCollector.php

@@ -174,7 +174,12 @@ class ExperimentFunnelCollector
                             }
 
                             $row['mrrCents'] += (int) ($monthlyEquiv[$priceId] ?? 0);
-                        } else {
+                        } elseif ($subscription === null || $subscription->refunded_at !== null) {
+                            // Burn = connections of matured users who never earned
+                            // net revenue: connected a bank but never carded, or
+                            // paid and got refunded. A user who paid and later
+                            // churned (canceled, not refunded) did convert, so
+                            // their connection cost is not burn.
                             $row['wastedCostCents'] += $connectionCostCents;
                         }
                     }

tests/Feature/SendExperimentFunnelReportCommandTest.php

@@ -248,6 +248,25 @@ it('reports a matured-cohort conversion capped at 100% and prints the matured de
         ->assertSuccessful();
 });
 
+it('excludes churned payers from burn but keeps refunds as burn', function () {
+    $signup = CarbonImmutable::parse('2026-06-05');
+
+    // Paid then canceled (not refunded): converted, so its cost is NOT burn.
+    experimentUser(SubscriptionExperiment::CONTROL, $signup, [
+        'status' => 'canceled', 'at' => $signup, 'endsAt' => $signup->addDays(20),
+    ], connections: 2);
+    // Paid then refunded: zero net revenue, so its cost IS burn.
+    experimentUser(SubscriptionExperiment::CONTROL, $signup, [
+        'status' => 'canceled', 'at' => $signup, 'endsAt' => $signup->addDay(), 'refundedAt' => $signup->addDay(),
+    ], connections: 3);
+
+    $control = app(ExperimentFunnelCollector::class)->collect()['variants'][SubscriptionExperiment::CONTROL];
+
+    expect($control['costCents'])->toBe(200)          // (2 + 3) × 40, all mature connections
+        ->and($control['wastedCostCents'])->toBe(120) // only the refunded user's 3 × 40
+        ->and($control['refunded'])->toBe(1);
+});
+
 it('scales connection cost by the cost-per-connection argument', function () {
     $signup = CarbonImmutable::parse('2026-06-05');