feat(admin): dock ticket reply composer in conversation and move notes to a dialog

Put the reply composer at the bottom of the conversation card so the
timeline and composer form one viewport-height panel; the send button is
visible on load and Ctrl/Cmd+Enter submits. Internal notes now open in a
dialog instead of expanding inline, so the sidebar no longer grows.

Remove the shared ticket_composer helper and the inline note expansion CSS;
both dialogs share ticket_dialog_head.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

assets/css/admin/tickets.css

@@ -1,4 +1,4 @@
-/* 工单运营页：列表、处理工作区（?id=）与代客提交（?view=new）均为页内视图。复用 NativeUi 令牌。 */
+/* 工单运营页：列表与处理工作区（?id=）为页内视图，代客提交与内部备注为原生 dialog。复用 NativeUi 令牌。 */
 .aksrt-tickets-admin__toolbar { display: flex; flex-direction: column; gap: 14px; padding: 20px; }
 .aksrt-tickets-admin__toolbar .subsubsub { margin: 0; padding: 0; box-shadow: none; }
 .aksrt-tickets-admin__table { min-width: 1000px; table-layout: fixed; }
@@ -57,22 +57,23 @@
 /* 侧栏在页面滚动时吸顶（让出 WP 管理工具栏），超出视口高度时栏内滚动。 */
 .aksrt-ticket-detail__side { position: sticky; top: 48px; max-height: calc(100vh - 64px); overflow-y: auto; overscroll-behavior: contain; scrollbar-width: thin; }
 .aksrt-ticket-conversation,
-.aksrt-ticket-composer--reply,
 .aksrt-ticket-detail__card { background: var(--an-card); border: 1px solid var(--an-border); border-radius: var(--an-radius); }
+/* 会话面板（IM 式）：头部、时间线、回复框同属一张卡片；卡片高度跟随视口，开屏即可看到回复框与发送按钮，只有时间线滚动。 */
+.aksrt-ticket-conversation { display: flex; flex-direction: column; height: calc(100vh - 200px); min-height: 460px; overflow: hidden; }
 .aksrt-ticket-detail__card { padding: 16px; }
 .aksrt-ticket-section-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px; margin-bottom: 14px; }
 .aksrt-ticket-section-head h3 { display: inline-flex; align-items: center; gap: 6px; margin: 0; color: var(--an-text); font-size: 14px; font-weight: 600; }
 .aksrt-ticket-section-head .button-link { font-size: 12px; text-decoration: none; }
-.aksrt-ticket-conversation > .aksrt-ticket-section-head { margin: 0; padding: 12px 16px; border-bottom: 1px solid var(--an-border-soft); }
+.aksrt-ticket-conversation > .aksrt-ticket-section-head { flex: none; margin: 0; padding: 12px 16px; border-bottom: 1px solid var(--an-border-soft); }
 
 /* 会话时间线：用户在左、客服在右、系统事件居中。 */
-.aksrt-ticket-conversation__scroll { max-height: 60vh; padding: 20px 16px; overflow-y: auto; overscroll-behavior: contain; }
+.aksrt-ticket-conversation__scroll { flex: 1 1 auto; min-height: 0; padding: 20px 16px; background: var(--an-bg-soft); overflow-y: auto; overscroll-behavior: contain; }
 .aksrt-ticket-detail__thread { display: flex; flex-direction: column; gap: 18px; margin: 0; padding: 0; list-style: none; }
 .aksrt-ticket-detail__message { display: flex; align-items: flex-start; gap: 10px; max-width: 86%; margin: 0; }
 .aksrt-ticket-detail__message.is-admin { flex-direction: row-reverse; align-self: flex-end; }
 .aksrt-ticket-detail__message.is-origin { max-width: none; }
 .aksrt-ticket-detail__avatar { flex: none; width: 32px; height: 32px; background: var(--an-border); border-radius: 50%; object-fit: cover; }
-.aksrt-ticket-detail__bubble { min-width: 0; padding: 10px 14px 12px; background: var(--an-bg-soft); border: 1px solid var(--an-border-soft); border-radius: 4px 12px 12px 12px; }
+.aksrt-ticket-detail__bubble { min-width: 0; padding: 10px 14px 12px; background: var(--an-card); border: 1px solid var(--an-border); border-radius: 4px 12px 12px 12px; }
 .aksrt-ticket-detail__message.is-admin .aksrt-ticket-detail__bubble { background: var(--an-primary-soft); border-color: color-mix(in srgb, var(--an-primary) 20%, transparent); border-radius: 12px 4px 12px 12px; }
 .aksrt-ticket-detail__message.is-origin .aksrt-ticket-detail__bubble { flex: 1; background: var(--an-card); border-color: var(--an-border); border-left: 3px solid var(--an-info); border-radius: 4px 12px 12px 12px; }
 .aksrt-ticket-detail__meta { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 8px; margin-bottom: 6px; font-size: 12px; }
@@ -94,11 +95,12 @@
 .aksrt-ticket-detail__attachments a:hover { transform: translateY(-1px); }
 .aksrt-ticket-detail__attachments img { display: block; width: 72px; height: 72px; object-fit: cover; border: 1px solid var(--an-border); border-radius: 8px; }
 
-/* 输入器：文本框与工具栏合成一个可聚焦整体。 */
-.aksrt-ticket-composer { margin: 0; }
-.aksrt-ticket-composer--reply { padding: 14px 16px 16px; }
-.aksrt-ticket-composer__head { display: flex; flex-wrap: wrap; align-items: baseline; gap: 4px 10px; margin-bottom: 8px; }
-.aksrt-ticket-composer__head label { color: var(--an-text); font-size: 14px; font-weight: 600; }
+/* 回复框：固定在会话卡片底部，文本框与工具栏合成一个可聚焦整体。 */
+.aksrt-ticket-composer { flex: none; margin: 0; padding: 12px 16px 14px; background: var(--an-card); border-top: 1px solid var(--an-border-soft); }
+.aksrt-ticket-composer textarea { max-height: 30vh; }
+.aksrt-ticket-composer__bar .button .dashicons { margin: 0 4px 0 -2px; font-size: 16px; width: 16px; height: 16px; vertical-align: -3px; }
+.aksrt-ticket-composer__shortcut { margin-left: auto; }
+.aksrt-ticket-composer__shortcut + .aksrt-ticket-counter { margin-left: 0; }
 .aksrt-ticket-composer__box { background: var(--an-card); border: 1px solid var(--an-border); border-radius: var(--an-radius-sm); transition: border-color .15s, box-shadow .15s; }
 .aksrt-ticket-composer__box:focus-within { border-color: var(--an-primary); box-shadow: 0 0 0 2px color-mix(in srgb, var(--an-primary) 18%, transparent); }
 .aksrt-native .aksrt-ticket-composer__box textarea { display: block; padding: 10px 12px; background: transparent; border: 0; border-radius: var(--an-radius-sm) var(--an-radius-sm) 0 0; box-shadow: none; }
@@ -109,7 +111,7 @@
 .aksrt-ticket-counter { margin-left: auto; color: var(--an-muted); font-size: 12px; font-variant-numeric: tabular-nums; }
 .aksrt-ticket-counter.is-over { color: var(--an-danger); }
 .aksrt-native-field .aksrt-ticket-counter { align-self: flex-end; }
-.aksrt-ticket-detail__closed { display: flex; align-items: center; gap: 8px; margin: 0; padding: 14px 16px; color: var(--an-text-2); background: var(--an-card); border: 1px dashed var(--an-border); border-radius: var(--an-radius); font-size: 13px; }
+.aksrt-ticket-detail__closed { display: flex; flex: none; align-items: center; gap: 8px; margin: 0; padding: 14px 16px; color: var(--an-text-2); background: var(--an-card); border-top: 1px solid var(--an-border-soft); font-size: 13px; }
 .aksrt-ticket-detail__closed .dashicons { flex: none; color: var(--an-muted); }
 
 /* 工单信息：标签列固定宽度，可编辑项直接内联。 */
@@ -139,18 +141,22 @@
 .aksrt-ticket-detail__notes li { margin: 0; padding: 8px 10px; background: var(--an-card); border: 1px solid #f3e2b6; border-radius: var(--an-radius-sm); font-size: 13px; line-height: 1.6; overflow-wrap: anywhere; }
 .aksrt-ticket-detail__note-head { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 4px; margin-bottom: 4px; font-size: 12px; }
 .aksrt-ticket-detail__note-head time { color: var(--an-muted); font-variant-numeric: tabular-nums; }
-.aksrt-ticket-detail__private .aksrt-ticket-composer__box { border-color: #f3e2b6; }
-/* 备注输入平时收成一行；聚焦或已有内容时展开为多行并显示提交栏。卡片标题已说明用途，标签仅供读屏。 */
-.aksrt-ticket-composer--note .aksrt-ticket-composer__head { position: absolute; width: 1px; height: 1px; margin: -1px; padding: 0; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
-.aksrt-ticket-composer--note:not(:focus-within):has(textarea:placeholder-shown) textarea { height: 42px; min-height: 0; resize: none; overflow: hidden; }
-.aksrt-ticket-composer--note:not(:focus-within):has(textarea:placeholder-shown) .aksrt-ticket-composer__bar { display: none; }
+.aksrt-ticket-detail__private .aksrt-ticket-section-head .button .dashicons { margin: 0 2px 0 -4px; font-size: 14px; width: 14px; height: 14px; vertical-align: -2px; }
+.aksrt-ticket-detail__notes-empty { margin: 0; color: var(--an-muted); font-size: 12px; }
+
+/* 内部备注弹窗：窄版，计数器右对齐在输入框下方。 */
+.aksrt-ticket-dialog--note { width: min(560px, calc(100vw - 48px)); }
+.aksrt-ticket-dialog__counter { display: block; margin-top: 6px; text-align: right; }
 
 @media (max-width: 960px) {
 	.aksrt-ticket-detail { grid-template-columns: minmax(0, 1fr); }
 	.aksrt-ticket-detail__side { position: static; max-height: none; overflow: visible; }
 }
 @media (max-width: 600px) {
-	.aksrt-ticket-conversation__scroll { max-height: 50vh; padding: 14px 12px; }
+	.aksrt-ticket-conversation { height: calc(100vh - 160px); min-height: 400px; }
+	.aksrt-ticket-conversation__scroll { padding: 14px 12px; }
+	.aksrt-ticket-composer { padding: 10px 12px 12px; }
+	.aksrt-ticket-composer__shortcut { display: none; }
 	.aksrt-ticket-detail__message { max-width: 100%; }
 	.aksrt-ticket-detail__avatar { width: 28px; height: 28px; }
 	.aksrt-ticket-composer__bar select { flex-basis: 100%; max-width: 100%; }