seed: add a starter Tracecoin package per role; fix paise unit bug in invoice line item

Seeds one TRACECOIN_BUNDLE package per role (100 Tracecoins / ₹250,
placeholder pricing per your instruction) so the purchase flow
(CreditsPage.tsx -> GET /api/packages, filtered client-side by
role_key) has something to show instead of "No packages available for
your role," and so create_order/verify_payment/invoice generation can
actually be exercised end-to-end. Idempotent (WHERE NOT EXISTS guard)
so it's safe against the custom db-migrate runner re-executing every
file on every deploy. Adjust real pricing later via the existing admin
CRUD (POST/PATCH /api/packages) — no new endpoint needed, it already
works.

Also fixes a unit bug introduced in the invoice wiring last commit:
payments.amount_inr is already paise (copied straight from
pricing_packages.price_inr, which is paise despite the name — PayU
order creation divides it by 100 via paise_to_rupee_string), but the
invoice line item multiplied it by 100 again, making every generated
invoice show a 100x inflated amount.

apps/payments/src/main.rs

@@ -191,7 +191,10 @@ async fn generate_purchase_invoice(
         description,
         hsn_sac_code: None,
         quantity: 1.0,
-        unit_price_paise: (payment.amount_inr as i64) * 100,
+        // payments.amount_inr is already paise (copied straight from
+        // pricing_packages.price_inr, itself paise despite the name — see
+        // payu::paise_to_rupee_string dividing by 100), not rupees.
+        unit_price_paise: payment.amount_inr as i64,
         tax_rate_percent: 18.0,
         metadata: payment.package_id.map(|id| serde_json::json!({ "package_id": id })),
     };

crates/db/migrations/20260721070000_seed_pricing_packages.down.sql

@@ -0,0 +1,2 @@
+DELETE FROM pricing_packages
+WHERE name = 'Starter Pack' AND package_type = 'TRACECOIN_BUNDLE' AND price_inr = 25000;

crates/db/migrations/20260721070000_seed_pricing_packages.up.sql

@@ -0,0 +1,28 @@
+-- Seed one purchasable Tracecoin package per role so the purchase flow
+-- (CreditsPage.tsx -> GET /api/packages, filtered client-side by
+-- role_key) has something to show instead of "No packages available for
+-- your role." Placeholder pricing per user instruction: ₹250 flat
+-- (25000 paise — pricing_packages.price_inr is paise despite the name,
+-- see apps/payments/src/payu.rs::paise_to_rupee_string) for 100
+-- Tracecoins, across every role. Adjust via the existing admin API
+-- (POST/PATCH /api/packages) once real pricing is decided.
+INSERT INTO pricing_packages (name, role_key, package_type, tracecoins_amount, price_inr, description, is_active)
+SELECT 'Starter Pack', role_key, 'TRACECOIN_BUNDLE', 100, 25000, '100 Tracecoins', true
+FROM (VALUES
+    ('COMPANY'),
+    ('CUSTOMER'),
+    ('JOB_SEEKER'),
+    ('PHOTOGRAPHER'),
+    ('MAKEUP_ARTIST'),
+    ('TUTOR'),
+    ('DEVELOPER'),
+    ('VIDEO_EDITOR'),
+    ('GRAPHIC_DESIGNER'),
+    ('SOCIAL_MEDIA_MANAGER'),
+    ('FITNESS_TRAINER'),
+    ('CATERING_SERVICES'),
+    ('UGC_CONTENT_CREATOR')
+) AS roles(role_key)
+WHERE NOT EXISTS (
+    SELECT 1 FROM pricing_packages p WHERE p.role_key = roles.role_key
+);