chore: add Biome for lint and fix all lint errors

- Install @biomejs/biome as devDependency at root
- Configure biome.json with 2-space indent, double quotes, Tailwind CSS support
- Add lint/lint:fix/format/format:fix scripts to root and app package.json
- Fix noNonNullAssertion: env vars extracted to variables with suppression, <div role=button> replaced with <button>
- Fix noUnusedVariables: remove unused destructured vars
- Fix useIterableCallbackReturn: arrow functions with block body
- Fix noExplicitAny: recharts Tooltip formatters
- Fix noLabelWithoutControl: add htmlFor+id or use <span> for non-input labels
- Fix noStaticElementInteractions/useKeyWithClickEvents: role+keyboard events for overlays
- Fix noArrayIndexKey: use error string as key
- Fix CSS parse: enable tailwindDirectives parser
- Normalize formatting across 80 files with biome check --write

apps/backend/src/modules/expenses/handlers/importExpenses.ts

@@ -1,26 +1,26 @@
 import type { Context } from "hono";
-import { prisma } from "../../../lib/prisma";
+import { PaymentStatus } from "../../../generated/prisma/client";
 import { cache } from "../../../lib/cache";
 import { logger } from "../../../lib/logger";
-import { PaymentStatus } from "../../../generated/prisma/client";
+import { prisma } from "../../../lib/prisma";
 
 function parseAmount(raw: string): number | null {
   const cleaned = raw.replace("$", "").replace(/,/g, "").trim();
   if (!cleaned) return null;
   const n = Number(cleaned);
-  return isNaN(n) ? null : n;
+  return Number.isNaN(n) ? null : n;
 }
 
 function parseDate(raw: string): Date | null {
   const trimmed = raw.trim();
   if (!trimmed) return null;
   const d = new Date(trimmed);
-  return isNaN(d.getTime()) ? null : d;
+  return Number.isNaN(d.getTime()) ? null : d;
 }
 
 export async function importExpensesHandler(c: Context) {
   const body = await c.req.parseBody();
-  const file = body["file"];
+  const file = body.file;
 
   if (!file || !(file instanceof File)) {
     return c.json({ error: "No se envió ningún archivo" }, 400);
@@ -30,7 +30,10 @@ export async function importExpensesHandler(c: Context) {
   const lines = text.trim().split("\n");
 
   if (lines.length < 2) {
-    return c.json({ error: "El archivo está vacío o solo tiene encabezados" }, 400);
+    return c.json(
+      { error: "El archivo está vacío o solo tiene encabezados" },
+      400,
+    );
   }
 
   let imported = 0;
@@ -43,7 +46,9 @@ export async function importExpensesHandler(c: Context) {
 
     const parts = line.split("|");
     if (parts.length < 10) {
-      errors.push(`Línea ${i + 1}: formato inválido (${parts.length} columnas)`);
+      errors.push(
+        `Línea ${i + 1}: formato inválido (${parts.length} columnas)`,
+      );
       continue;
     }
 
@@ -68,7 +73,9 @@ export async function importExpensesHandler(c: Context) {
       const paymentDate = parseDate(rawPaymentDate);
 
       if (!dueDate) {
-        errors.push(`Línea ${i + 1} ("${description}"): fecha de vencimiento inválida`);
+        errors.push(
+          `Línea ${i + 1} ("${description}"): fecha de vencimiento inválida`,
+        );
         continue;
       }
 
@@ -90,7 +97,8 @@ export async function importExpensesHandler(c: Context) {
         }
       }
 
-      const status = rawStatus === "PAYED" ? PaymentStatus.PAYED : PaymentStatus.PENDING;
+      const status =
+        rawStatus === "PAYED" ? PaymentStatus.PAYED : PaymentStatus.PENDING;
 
       await prisma.expense.create({
         data: {