fix: match scenario 2601 monthly seed progression

packages/logic/src/compat/legacyFloat.ts

@@ -0,0 +1,10 @@
+// MariaDB FLOAT stores binary32, but its text protocol exposes only six
+// significant decimal digits. Ref reads that text into PHP before every
+// command/battle update, so both boundaries are part of the game state.
+export const toLegacyStoredFloat = (value: number): number => Math.fround(value);
+
+export const readLegacyStoredFloat = (value: number): number =>
+    Number(Math.fround(value).toPrecision(6));
+
+export const addLegacyStoredFloat = (current: number, delta: number): number =>
+    toLegacyStoredFloat(readLegacyStoredFloat(current) + delta);