Account Modal Bugfix (#3687)

## Description:

Fix null stat values from LEFT JOIN causing Zod validation failure on
player profiles

https://github.com/openfrontio/infra/pull/316 switched playerStats from
innerJoin to leftJoin so that sessions with no stats row (games that
ended instantly on spawn) are still counted in wins/losses/total.


## Please complete the following:

- [x] I have added screenshots for all UI updates
- [x] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [x] I have added relevant tests to the test directory
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

## Please put your Discord username so you can be contacted if a bug or
regression is found:

w.o.n

src/core/StatsSchemas.ts

@@ -94,6 +94,7 @@ export const OTHER_INDEX_LOST = 3; // Structures/warships destroyed/captured by
 export const OTHER_INDEX_UPGRADE = 4; // Structures upgraded
 
 export const BigIntStringSchema = z.preprocess((val) => {
+  if (val === null) return 0n;
   if (typeof val === "string" && /^-?\d+$/.test(val)) return BigInt(val);
   if (typeof val === "bigint") return val;
   return val;

tests/StatsSchema.test.ts

@@ -1,3 +1,4 @@
+import { PlayerStatsLeafSchema } from "../src/core/ApiSchemas";
 import { PlayerStatsSchema } from "../src/core/StatsSchemas";
 
 function testPlayerSchema(
@@ -45,4 +46,32 @@ describe("StatsSchema", () => {
     testPlayerSchema("{", false, true);
     testPlayerSchema("{}}", false, true);
   });
+
+  test("null array elements coerce to 0n (LEFT JOIN rows with no stats)", () => {
+    // Postgres SUM() over all-NULL rows returns NULL. These should parse as 0n.
+    testPlayerSchema(
+      '{"attacks":[null,null,null],"betrayals":null,"gold":[null,null,null,null,null,null]}',
+    );
+  });
+});
+
+describe("PlayerStatsLeafSchema", () => {
+  test("null stat values coerce to 0n", () => {
+    const result = PlayerStatsLeafSchema.safeParse({
+      wins: "0",
+      losses: "1",
+      total: "1",
+      stats: { attacks: [null, null, null], betrayals: null },
+    });
+    expect(result.success).toBe(true);
+  });
+
+  test("missing required field (wins) still fails — undefined is not coerced", () => {
+    const result = PlayerStatsLeafSchema.safeParse({
+      losses: "1",
+      total: "1",
+      stats: {},
+    });
+    expect(result.success).toBe(false);
+  });
 });