feat(themes): confirm uninstalls and restore tab padding

Add a confirmation dialog before removing an installed theme, warning
that local edits are deleted. Apply content padding to the absolute tab
panels so the workshop and library views stay inset from the frame.

src/screens/Launch.svelte

@@ -313,6 +313,8 @@
   };
   let restoreCandidate = $state<{ theme: Theme; backup: ThemeBackup } | undefined>(undefined);
   let restoringTheme = $state(false);
+  let uninstallCandidate = $state<Theme | undefined>(undefined);
+  let uninstallingTheme = $state(false);
   let installedReportOpen = $state(false);
   let installedReportTarget = $state<CommunityTheme | null>(null);
   let installedReportLoading = $state(false);
@@ -528,6 +530,9 @@
   };
 
   const uninstallInstalledTheme = async (theme: Theme) => {
+    if (uninstallingTheme) return false;
+    uninstallingTheme = true;
+
     try {
       const deleteResult = await deleteTheme(theme);
       if (deleteResult) {
@@ -535,18 +540,36 @@
           title: 'Theme uninstalled',
           description: `"${theme.name}" was removed from your library.`,
         });
-      } else {
+        return true;
+      }
+
       sileo.error({
         title: 'Could not uninstall theme',
         description: 'The theme files could not be removed.',
       });
-      }
+      return false;
     } catch (err) {
       console.error(err);
       sileo.error({
         title: 'Could not uninstall theme',
         description: err instanceof Error ? err.message : String(err),
       });
+      return false;
+    } finally {
+      uninstallingTheme = false;
+    }
+  };
+
+  const requestThemeUninstall = (theme: Theme) => {
+    if (theme.status !== 'installed' || theme.name === 'Default' || uninstallingTheme) return;
+    uninstallCandidate = theme;
+  };
+
+  const confirmThemeUninstall = async () => {
+    const theme = uninstallCandidate;
+    if (!theme) return;
+    if (await uninstallInstalledTheme(theme)) {
+      uninstallCandidate = undefined;
     }
   };
 
@@ -2404,6 +2427,51 @@
   </AlertDialog.Content>
 </AlertDialog.Root>
 
+<AlertDialog.Root open={uninstallCandidate !== undefined}>
+  <AlertDialog.Content
+    class="bg-theme-950 border-theme-800 p-0 max-w-xl"
+    escapeKeydownBehavior="ignore"
+    interactOutsideBehavior="ignore"
+  >
+    <div
+      class="flex flex-col items-center justify-center gap-2 border-b border-theme-800 bg-black/40 rounded-t-lg p-4"
+    >
+      <ThemeIcon name="trash" set={iconSet} class="size-7 text-red-300" />
+      <span class="font-semibold text-lg">Uninstall theme?</span>
+    </div>
+    <div
+      class="mx-3 mt-3 rounded-lg border border-theme-800 bg-theme-900 p-3 text-xs leading-relaxed text-muted-foreground"
+    >
+      Remove <strong class="text-theme-100">{uninstallCandidate?.name}</strong> from your library? This
+      deletes the local theme files and any unpublished changes. If the theme is published to the Workshop,
+      that copy is not affected.
+    </div>
+    <div class="flex items-center justify-center gap-3 p-4">
+      <Button
+        variant="outline"
+        class="min-w-28"
+        disabled={uninstallingTheme}
+        onclick={() => (uninstallCandidate = undefined)}
+      >
+        Cancel
+      </Button>
+      <Button
+        variant="destructive"
+        class="min-w-28"
+        disabled={uninstallingTheme}
+        onclick={confirmThemeUninstall}
+      >
+        {#if uninstallingTheme}
+          <ThemeIcon name="loader" set={iconSet} class="animate-spin" />
+        {:else}
+          <ThemeIcon name="trash" set={iconSet} class="size-4" />
+        {/if}
+        {uninstallingTheme ? 'Uninstalling...' : 'Uninstall theme'}
+      </Button>
+    </div>
+  </AlertDialog.Content>
+</AlertDialog.Root>
+
 <AlertDialog.Root open={pendingExternalUrl !== undefined}>
   <AlertDialog.Content
     class="bg-theme-950 border-theme-800 p-0 max-w-xl"
@@ -4225,10 +4293,10 @@
               {/if}
             </header>
 
-            <div class="relative min-h-0 flex-1 px-5 pt-4 pb-1">
+            <div class="relative min-h-0 flex-1">
               {#if activeThemesTab === 'workshop'}
                 <div
-                  class="absolute inset-0"
+                  class="absolute inset-0 px-5 pt-4 pb-1"
                   in:fly={{ duration: $reduceAnimations ? 0 : 240, y: 8, opacity: 0 }}
                   out:fade={{ duration: $reduceAnimations ? 0 : 160 }}
                 >
@@ -4249,7 +4317,7 @@
                 </div>
               {:else}
                 <div
-                  class="absolute inset-0"
+                  class="absolute inset-0 px-5 pt-4 pb-1"
                   in:fly={{ duration: $reduceAnimations ? 0 : 240, y: 8, opacity: 0 }}
                   out:fade={{ duration: $reduceAnimations ? 0 : 160 }}
                 >
@@ -4590,11 +4658,13 @@
                                             </DropdownMenu.Item>
                                           {/if}
                                           {#if canUninstallTheme}
+                                            {#if canEditTheme || canRestoreTheme || canUpdateTheme || canReportTheme}
                                               <DropdownMenu.Separator class="my-1 bg-theme-800" />
+                                            {/if}
                                             <DropdownMenu.Item
                                               class="gap-2 text-[11px] text-red-300 data-[highlighted]:bg-red-500/15 data-[highlighted]:text-red-200"
                                               disabled={theme.status !== 'installed'}
-                                              onclick={() => void uninstallInstalledTheme(theme)}
+                                              onclick={() => requestThemeUninstall(theme)}
                                             >
                                               {#if theme.status === 'deleting'}
                                                 <ThemeIcon