polish(v0.6): make "New session" a grid tile instead of a heavy header button

The big solid-amber "+ New session" button clashed with the refined segmented
control. Replace it with a dashed "+" tile that leads the session grid (same
size as the session cards, re-prepended each refresh), so it reads as a natural
"create" cell. Header is now just the title + Sessions/Projects toggle; the
redundant empty-state message is gone (the tile is the CTA).

Frontend-only (launcher.ts + style.css). Verified: web typecheck + build clean,
preview-grid tests green, in-browser the grid leads with the New-session tile
followed by the session cards (Open/Kill).

docs/PROGRESS_LOG.md

@@ -146,6 +146,14 @@
 - **commit**: <hash 或 N/A>
 ======================================================= -->
 
+### 2026-06-30 · v0.6 "New session" 改为网格卡片(去掉别扭的大按钮)
+
+- **状态**: `[x]` DONE。web typecheck 干净 · `build:web` OK · 真浏览器验证通过。
+- **需求**(用户): 头部那个大的实心琥珀 "＋ New session" 按钮很别扭(与精致的分段 pill 不协调)。
+- **改动**(纯前端 `public/launcher.ts` + style): 删头部 `.launcher-new` 按钮 + `.launcher-actions`;改为 grid 内的 **`.mg-new-card` 虚线"＋ New session"瓦片**(与 session 卡同尺寸,始终排在网格第一格,每次 refresh 重新 prepend),hover 变琥珀。删冗余 `.mg-empty` 空态(瓦片即 CTA)。头部只剩标题 + 段控,更干净。
+- **验证**: `npx tsc -p tsconfig.web.json` 干净;`build:web` OK;`preview-grid` 测试 14 全绿;真浏览器:Sessions 网格首格为虚线 New 瓦片 + 其后 session 卡(Open/Kill),无旧大按钮。
+- **commit**: (本次提交)
+
 ### 2026-06-30 · v0.6 删除 manage 独立页 — Sessions 选择器即会话管理
 
 - **状态**: `[x]` DONE。**453 测试全绿** · web typecheck 干净 · `build:web` OK(仅 main,无 manage 产物)· 真浏览器验证通过。

public/launcher.ts

@@ -42,16 +42,20 @@ export function mountLauncher(host: HTMLElement, hooks: LauncherHooks): Launcher
   const head = el('div', 'launcher-head')
   head.append(el('div', 'launcher-title', 'Your sessions'))
   const sub = el('div', 'launcher-sub', '')
-  const actions = el('div', 'launcher-actions')
-  const newBtn = el('button', 'launcher-new', '＋ New session')
-  newBtn.addEventListener('click', () => hooks.onNew())
-  actions.append(newBtn)
-  head.append(sub, actions)
+  head.append(sub)
   root.append(head)
 
   const grid = el('div', 'mg-grid')
   root.append(grid)
 
+  // "New session" is a tile that leads the grid (matches the session cards),
+  // instead of a heavy header button. Re-prepended on every refresh.
+  const newTile = el('button', 'mg-new-card')
+  newTile.title = 'Start a new session'
+  newTile.setAttribute('aria-label', 'New session')
+  newTile.append(el('div', 'mg-new-plus', '＋'), el('div', 'mg-new-label', 'New session'))
+  newTile.addEventListener('click', () => hooks.onNew())
+
   const cards = new Map<string, PreviewCard>()
   let timer: ReturnType<typeof setInterval> | null = null
 
@@ -78,6 +82,9 @@ export function mountLauncher(host: HTMLElement, hooks: LauncherHooks): Launcher
       ? `${sessions.length} running on this host — pick one to open`
       : 'No sessions running yet'
 
+    // Keep the New-session tile as the first grid cell.
+    if (grid.firstChild !== newTile) grid.prepend(newTile)
+
     const seen = new Set<string>()
     for (const s of sessions) {
       seen.add(s.id)
@@ -99,10 +106,6 @@ export function mountLauncher(host: HTMLElement, hooks: LauncherHooks): Launcher
       }
     }
 
-    grid.querySelector('.mg-empty')?.remove()
-    if (sessions.length === 0) {
-      grid.append(el('div', 'mg-empty', 'No running sessions. Click “New session” to start one.'))
-    }
   }
 
   return {

public/style.css

@@ -711,18 +711,35 @@ body {
   display: flex;
   gap: 8px;
 }
-.launcher-new {
-  background: var(--accent);
-  color: var(--on-accent);
-  border: none;
-  border-radius: 8px;
-  padding: 9px 16px;
-  font: inherit;
-  font-weight: 600;
+/* "New session" tile — leads the session grid, matching the session cards. */
+.mg-new-card {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  gap: 8px;
+  min-height: 200px;
+  background: none;
+  border: 2px dashed var(--border-strong);
+  border-radius: 12px;
+  color: var(--text-dim);
   cursor: pointer;
+  font: inherit;
+  transition: border-color 0.12s ease, color 0.12s ease, background 0.12s ease;
 }
-.launcher-new:hover {
-  background: var(--accent-2);
+.mg-new-card:hover {
+  border-color: var(--accent);
+  color: var(--accent);
+  background: var(--accent-soft);
+}
+.mg-new-plus {
+  font-size: 34px;
+  font-weight: 300;
+  line-height: 1;
+}
+.mg-new-label {
+  font-size: 14px;
+  font-weight: 600;
 }
 
 /* ── Session Manager page (manage.html) ──────────────────────────── */