feat(ui): resizable/hideable meetings-list and summary panes

Left (meetings list) and right (summary) panes gain drag-to-resize via
Splitter and a collapse/expand toggle (thin rail + panel icon), sizes
and collapsed state persisted via the layout store.

src/App.svelte

@@ -14,7 +14,19 @@
   import { api, type NoteTemplate } from "./lib/api";
   import { onMount } from "svelte";
   import ThemeToggle from "./lib/components/ThemeToggle.svelte";
-  import { Circle, Square, Trash2, Settings as SettingsIcon, AlertTriangle } from "@lucide/svelte";
+  import Splitter from "./lib/components/Splitter.svelte";
+  import { layout, clamp } from "./lib/stores/layout.svelte";
+  import {
+    Circle,
+    Square,
+    Trash2,
+    Settings as SettingsIcon,
+    AlertTriangle,
+    PanelLeftClose,
+    PanelLeftOpen,
+    PanelRightClose,
+    PanelRightOpen,
+  } from "@lucide/svelte";
 
   let showSettings = $state(false);
   let showConsent = $state(false);
@@ -291,10 +303,89 @@
     </div>
   {/if}
 
-  <main class="panes">
-    <aside class="left"><MeetingsList /></aside>
+  <main
+    class="panes"
+    style="grid-template-columns: {layout.leftCollapsed
+      ? 'auto'
+      : layout.leftWidth + 'px'} auto 1fr auto {layout.rightCollapsed
+      ? 'auto'
+      : layout.rightWidth + 'px'};"
+  >
+    <aside class="side left" class:collapsed={layout.leftCollapsed}>
+      {#if layout.leftCollapsed}
+        <button
+          class="pane-toggle"
+          onclick={() => {
+            layout.leftCollapsed = false;
+            layout.persist();
+          }}
+          title="Show meetings list"
+          aria-label="Show meetings list"
+        >
+          <PanelLeftOpen size={16} aria-hidden="true" />
+        </button>
+      {:else}
+        <button
+          class="pane-toggle inline"
+          onclick={() => {
+            layout.leftCollapsed = true;
+            layout.persist();
+          }}
+          title="Hide meetings list"
+          aria-label="Hide meetings list"
+        >
+          <PanelLeftClose size={14} aria-hidden="true" />
+        </button>
+        <div class="side-content"><MeetingsList /></div>
+      {/if}
+    </aside>
+    {#if !layout.leftCollapsed}
+      <Splitter
+        label="Resize meetings list"
+        onResize={(d) => (layout.leftWidth = clamp(layout.leftWidth + d, 200, 480))}
+        onResizeEnd={() => layout.persist()}
+      />
+    {:else}
+      <span></span>
+    {/if}
     <section class="center"><TranscriptNotes /></section>
-    <aside class="right"><SummaryPanel /></aside>
+    {#if !layout.rightCollapsed}
+      <Splitter
+        label="Resize summary panel"
+        onResize={(d) => (layout.rightWidth = clamp(layout.rightWidth - d, 240, 560))}
+        onResizeEnd={() => layout.persist()}
+      />
+    {:else}
+      <span></span>
+    {/if}
+    <aside class="side right" class:collapsed={layout.rightCollapsed}>
+      {#if layout.rightCollapsed}
+        <button
+          class="pane-toggle"
+          onclick={() => {
+            layout.rightCollapsed = false;
+            layout.persist();
+          }}
+          title="Show summary panel"
+          aria-label="Show summary panel"
+        >
+          <PanelRightOpen size={16} aria-hidden="true" />
+        </button>
+      {:else}
+        <button
+          class="pane-toggle inline"
+          onclick={() => {
+            layout.rightCollapsed = true;
+            layout.persist();
+          }}
+          title="Hide summary panel"
+          aria-label="Hide summary panel"
+        >
+          <PanelRightClose size={14} aria-hidden="true" />
+        </button>
+        <div class="side-content"><SummaryPanel /></div>
+      {/if}
+    </aside>
   </main>
 </div>
 
@@ -592,25 +683,56 @@
   }
   .panes {
     display: grid;
-    grid-template-columns: 260px 1fr 320px;
+    /* grid-template-columns set inline — depends on collapse/resize state (FR-UX-1). */
     flex: 1;
     min-height: 0;
   }
-  .left,
-  .right {
+  .side {
+    display: flex;
+    flex-direction: column;
+    min-height: 0;
     border-color: var(--border);
-    overflow: auto;
     background: var(--bg-subtle);
   }
-  .left {
+  .side.left {
     border-right: 1px solid var(--border);
   }
-  .right {
+  .side.right {
     border-left: 1px solid var(--border);
   }
+  .side.collapsed {
+    align-items: center;
+    padding-top: 0.4rem;
+  }
+  .side-content {
+    flex: 1;
+    min-height: 0;
+    overflow: auto;
+  }
+  .pane-toggle {
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    flex: none;
+    background: none;
+    border: none;
+    color: var(--muted);
+    cursor: pointer;
+    padding: 0.4rem;
+    border-radius: var(--radius-sm);
+  }
+  .pane-toggle:hover {
+    background: var(--bg-hover);
+    color: var(--fg);
+  }
+  .pane-toggle.inline {
+    align-self: flex-end;
+    margin: 0.3rem 0.3rem 0;
+  }
   .center {
     overflow: auto;
     background: var(--bg);
+    min-width: 0;
   }
   .vault-overlay {
     position: fixed;