refactor: clean up ugly type casting patterns in billing package

- Replace `as unknown as` double-casts with cleaner alternatives:
  - balance-calculator.ts: use .then() handler for type assertion
  - credit-delegation.ts: use .then() handler for type assertion
  - grant-credits.ts: use direct type assertion (limit() returns sync)

- All billing files now use consistent, cleaner type patterns

Author: brandonkachen

packages/billing/src/balance-calculator.ts

@@ -715,7 +715,8 @@ export async function calculateUsageThisCycle(params: {
           ),
         ),
       ),
-    ) as unknown as { totalUsed: number }[]
+    )
+    .then(rows => rows as { totalUsed: number }[])
 
   return usageResult[0].totalUsed
 }

packages/billing/src/credit-delegation.ts

@@ -71,7 +71,8 @@ export async function findOrganizationForRepository(params: {
       })
       .from(schema.orgMember)
       .innerJoin(schema.org, eq(schema.orgMember.org_id, schema.org.id))
-      .where(eq(schema.orgMember.user_id, userId)) as unknown as { orgId: string; orgName: string; orgSlug: string }[]
+      .where(eq(schema.orgMember.user_id, userId))
+      .then(rows => rows as { orgId: string; orgName: string; orgSlug: string }[])
 
     if (userOrganizations.length === 0) {
       logger.debug(
@@ -95,7 +96,8 @@ export async function findOrganizationForRepository(params: {
             eq(schema.orgRepo.org_id, userOrg.orgId),
             eq(schema.orgRepo.is_active, true),
           ),
-        ) as unknown as { repoUrl: string; repoName: string; isActive: boolean }[]
+        )
+        .then(rows => rows as { repoUrl: string; repoName: string; isActive: boolean }[])
 
       // Check if any repository in this organization matches
       for (const orgRepo of orgRepos) {

packages/billing/src/grant-credits.ts

@@ -55,7 +55,7 @@ export async function getPreviousFreeGrantAmount(params: {
       ),
     )
     .orderBy(desc(schema.creditLedger.expires_at)) // Most recent expiry first
-    .limit(1) as unknown as { principal: number }[]
+    .limit(1) as { principal: number }[]
 
   if (lastExpiredFreeGrant.length > 0) {
     // TODO: remove this once it's past May 22nd, after all users have been migrated over
@@ -107,7 +107,7 @@ export async function calculateTotalReferralBonus(params: {
           eq(schema.referral.referrer_id, userId),
           eq(schema.referral.referred_id, userId),
         ),
-      ) as unknown as { totalCredits: string }[]
+      ) as { totalCredits: string }[]
 
     const totalBonus = parseInt(result[0]?.totalCredits ?? '0')
     logger.debug({ userId, totalBonus }, 'Calculated total referral bonus.')