style(comments): tighten aside panel spacing and widen it

- Widen the comments/aside panel from 350 to 420 (~20% wider)
- Remove double padding around the panel: AppShell.Aside p="md"->"sm"
  and inner Box p="md"->p={0}; reduce header-to-tabs gap mb="md"->"sm"
- Reduce empty space below the add-comment input (paddingBottom 25->10),
  align the avatar with the input box (marginTop 10->2) and re-anchor the
  send button (bottom 30->15)
- Pull the timestamp closer to the nickname via tighter line-height
  (lh 1.2 on the name, 1.1 on the "… ago" text)

apps/client/src/components/layouts/global/aside.tsx

@@ -44,10 +44,10 @@ export default function Aside() {
   }
 
   return (
-    <Box p="md" style={{ height: "100%", display: "flex", flexDirection: "column" }}>
+    <Box p={0} style={{ height: "100%", display: "flex", flexDirection: "column" }}>
       {component && (
         <>
-          <Group justify="space-between" wrap="nowrap" mb="md">
+          <Group justify="space-between" wrap="nowrap" mb="sm">
             <Title order={2} size="h6" fw={500}>{t(title)}</Title>
             <Tooltip label={t("Close")} withArrow>
               <ActionIcon

apps/client/src/components/layouts/global/global-app-shell.tsx

@@ -94,7 +94,7 @@ export default function GlobalAppShell({
       }}
       aside={
         isPageRoute && {
-          width: 350,
+          width: 420,
           breakpoint: "sm",
           collapsed: { mobile: !isAsideOpen, desktop: !isAsideOpen },
         }
@@ -138,7 +138,7 @@ export default function GlobalAppShell({
           id={ASIDE_PANEL_ID}
           tabIndex={-1}
           className={classes.aside}
-          p="md"
+          p="sm"
           withBorder={false}
           aria-label={
             asideTab === "comments"