Fix dailyLog date query to use proper date comparison

- Change /api/today query from string contains (~) to date range (>=, <)
- Store dates in full ISO format in garmin-sync for consistent comparison
- PocketBase date fields need proper date operators, not string contains

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/api/today/route.ts

@@ -74,13 +74,24 @@ export const GET = withAuth(async (_request, user, pb) => {
   // Sort by created DESC to get the most recent record if multiple exist
   let biometrics = { ...DEFAULT_BIOMETRICS, phaseLimit };
   try {
-    const today = new Date().toISOString().split("T")[0];
-    logger.info({ userId: user.id, today }, "Fetching dailyLog");
+    // Use date range query for proper date field comparison
+    // PocketBase date fields need >= and < operators, not string contains
+    const todayStart = new Date();
+    todayStart.setUTCHours(0, 0, 0, 0);
+    const tomorrowStart = new Date(todayStart.getTime() + 86400000);
+    const todayISO = todayStart.toISOString();
+    const tomorrowISO = tomorrowStart.toISOString();
+
+    logger.info(
+      { userId: user.id, todayISO, tomorrowISO },
+      "Fetching dailyLog",
+    );
     const dailyLog = await pb
       .collection("dailyLogs")
-      .getFirstListItem<DailyLog>(`user="${user.id}" && date~"${today}"`, {
-        sort: "-created",
-      });
+      .getFirstListItem<DailyLog>(
+        `user="${user.id}" && date>="${todayISO}" && date<"${tomorrowISO}"`,
+        { sort: "-created" },
+      );
 
     logger.info(
       {