feat(app): embed indexer in Electron with file-watching service and UI refinements

Extract schema DDL into scripts/schema.sql shared between CLI and app.
  Add an in-process chokidar-based indexer-service that watches ~/.claude/projects
  for JSONL changes, debounces, and triggers background rebuilds via a worker
  thread. Rename Usage view to Activity, flesh out MemoryDetail and SubagentDetail
  views, and refine App.vue layout/routing. The main process now starts/stops the
  indexer lifecycle and notifies renderer windows on index updates.

app/renderer/styles/list.css

@@ -116,6 +116,10 @@
     content: ''; position: absolute; left: 0; top: 0; bottom: 0;
     width: 2px; background: var(--muted-2);
   }
+  .srow-obelisk {
+    position: absolute; left: 0; bottom: 0;
+    width: 3px; border-radius: 1.5px 1.5px 0 0;
+  }
   .srow-body { min-width: 0; display: flex; flex-direction: column; gap: 4px; }
   .srow-title {
     font-size: var(--text-md); font-weight: 500; color: var(--fg);
@@ -146,7 +150,9 @@
     color: var(--fg-2); text-align: right;
     font-variant-numeric: tabular-nums;
     flex-shrink: 0; padding-top: 2px; white-space: nowrap;
+    display: flex; flex-direction: column; gap: 2px;
   }
+  .srow-right .srow-created { font-size: 10px; color: var(--muted); }
 
   .empty {
     flex: 1; display: flex; align-items: center; justify-content: center;

app/renderer/styles/sidebar.css

@@ -34,7 +34,7 @@
 .sidebar-search input::placeholder { color: var(--muted-2); }
 .sidebar-search input:focus { outline: 0; border-color: var(--accent); background: var(--surface-strong); }
 .sidebar-search-icon {
-  position: absolute; left: 14px; top: 50%; transform: translateY(-50%);
+  position: absolute; left: 14px; top: 12px; transform: translateY(-50%);
   width: 11px; height: 11px; color: var(--muted); pointer-events: none;
 }
 .sidebar-list { overflow-y: auto; padding: 2px 0 8px; flex: 1; min-height: 0; }

app/renderer/styles/toolbar.css

@@ -15,7 +15,7 @@
     cursor: pointer; transition: all 0.1s;
     display: inline-flex; align-items: center; gap: 6px;
     line-height: 1; border: 0; background: transparent;
-    white-space: nowrap;
+    white-space: nowrap; text-decoration: none;
   }
   .crumb:hover { background: var(--surface-strong); color: var(--fg-2); }
   .crumb.terminal { color: var(--fg); font-weight: 600; cursor: default; }