Fix week view time grid display and late night event rendering

- Remove unnecessary boundary slot from week view time grid
- Adjust container heights to display full 11 PM - midnight time slot
- Fix timezone issue preventing events at 8 PM or later from rendering
- Update date matching logic to handle UTC-4 timezone offset correctly

🤖 Generated with [Claude Code](https://claude.ai/code)

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

frontend/styles.css

@@ -685,12 +685,13 @@ body {
     flex: 1;
     overflow-y: auto;
     overflow-x: hidden;
+    min-height: 0; /* Allow flex item to shrink below content size */
 }
 
 .time-grid {
     display: grid;
     grid-template-columns: 80px 1fr;
-    min-height: 100%;
+    min-height: 1530px;
 }
 
 /* Time Labels */
@@ -700,6 +701,7 @@ body {
     position: sticky;
     left: 0;
     z-index: 5;
+    min-height: 1440px; /* Match the time slots height */
 }
 
 .time-label {
@@ -725,12 +727,13 @@ body {
 .week-days-grid {
     display: grid;
     grid-template-columns: repeat(7, 1fr);
+    min-height: 1440px; /* Ensure grid is tall enough for 24 time slots */
 }
 
 .week-day-column {
     position: relative;
     border-right: 1px solid var(--time-label-border, #e9ecef);
-    min-height: 1500px; /* 25 time labels × 60px = 1500px total */
+    min-height: 1440px; /* 24 time slots × 60px = 1440px total */
 }
 
 .week-day-column:last-child {