refactor(ui): modernize status bar and component structure

This commit introduces a comprehensive overhaul of the application's UI, focusing on modernizing the global workspace status bar and improving overall theming consistency. Several components were refactored to simplify prop handling and improve separation of concerns, particularly within the TitleBar and RepoToolbar. The CSS includes extensive new variables and styles for better visual fidelity across light and dark themes.

- Overhauled the main application footer to display version, branch status, and sync metrics.
- Added global CSS variables and component styling for a modern look.
- Simplified repository state management by removing redundant props from TitleBar.

src/lib/components/LinePatchDialog.svelte

@@ -47,6 +47,7 @@
   }: Props = $props();
 
   let parsed = $state<ParsedPatch>({ headerLines: [], hunks: [], binary: false });
+  let patchScroll = $state<HTMLDivElement | null>(null);
 
   let scopeLabel = $derived(staged ? "Staged changes" : "Unstaged changes");
   let displayPath = $derived(file.old_path ? `${file.old_path} -> ${file.path}` : file.path);
@@ -118,6 +119,23 @@
     if (isBusy || isLoading) return;
     await onApply(action, buildHunkPatch(hunk));
   }
+
+  function hunkPosition(index: number): number {
+    const totalLines = parsed.hunks.reduce((sum, hunk) => sum + Math.max(hunk.lines.length, 1), 0);
+    const precedingLines = parsed.hunks.slice(0, index).reduce((sum, hunk) => sum + Math.max(hunk.lines.length, 1), 0);
+    return (precedingLines / Math.max(totalLines - 1, 1)) * 100;
+  }
+
+  function hunkKind(hunk: PatchHunk): "add" | "delete" | "mixed" {
+    const hasAdd = hunk.lines.some((line) => line.kind === "add");
+    const hasDelete = hunk.lines.some((line) => line.kind === "delete");
+    return hasAdd && hasDelete ? "mixed" : hasAdd ? "add" : "delete";
+  }
+
+  function scrollToHunk(hunkId: string) {
+    const target = patchScroll?.querySelector<HTMLElement>(`[data-hunk-id="${hunkId}"]`);
+    if (patchScroll && target) patchScroll.scrollTop = Math.max(target.offsetTop - 8, 0);
+  }
 </script>
 
 <div class="dialog-backdrop" role="presentation">
@@ -148,9 +166,10 @@
       {:else if parsed.binary || parsed.hunks.length === 0}
         <div class="blank-state">This change cannot be split into text lines.</div>
       {:else}
-        <div class="line-patch-scroll">
+        <div class="line-patch-workspace">
+        <div class="line-patch-scroll" bind:this={patchScroll}>
           {#each parsed.hunks as hunk (hunk.id)}
-            <section class="line-patch-hunk">
+            <section class="line-patch-hunk" data-hunk-id={hunk.id}>
               <div class="line-patch-hunk-head">
                 <code>{hunk.header}</code>
                 <div class="line-patch-hunk-actions">
@@ -183,6 +202,19 @@
             </section>
           {/each}
         </div>
+        <nav class="diff-overview line-patch-overview" aria-label="Change overview">
+          {#each parsed.hunks as hunk, index (hunk.id)}
+            <button
+              class="diff-overview-marker {hunkKind(hunk)}"
+              type="button"
+              style={`--marker-position: ${hunkPosition(index)}%`}
+              onclick={() => scrollToHunk(hunk.id)}
+              title={`Jump to hunk ${index + 1} of ${parsed.hunks.length}`}
+              aria-label={`Jump to hunk ${index + 1} of ${parsed.hunks.length}`}
+            ></button>
+          {/each}
+        </nav>
+        </div>
       {/if}
     </div>
   </div>