fix: correct messages layout height units and remove autofocus scroll

- Replace `100vh` with `100dvh` in messages-layout height and min-height to properly account for mobile browser dynamic toolbar heights, adjusting offset from 2rem to 3.5rem for consistent spacing
- Remove `autofocus` attribute from message input field to prevent automatic keyboard popup on page load
- Remove `footer` block override that was incorrectly suppressing the site footer on messages page
- Change `input.focus()` to `input.focus({ preventScroll: true })` in the scroll-to-bottom script to avoid unwanted page jumps when focusing the input after sending a message

devplacepy/static/css/messages.css

@@ -2,7 +2,7 @@
     display: grid;
     grid-template-columns: minmax(0, 320px) 1fr;
     gap: 0;
-    height: calc(100vh - var(--nav-height) - 2rem);
+    height: calc(100dvh - var(--nav-height) - 3.5rem);
     background: var(--bg-card);
     border: 1px solid var(--border);
     border-radius: var(--radius-lg);
@@ -247,7 +247,7 @@
     .messages-layout {
         grid-template-columns: 1fr;
         height: auto;
-        min-height: calc(100vh - var(--nav-height) - 2rem);
+        min-height: calc(100dvh - var(--nav-height) - 3.5rem);
     }
     .messages-list {
         display: flex;