refactor: render the shell in the client (#3487)

* feat: add opt-in client-rendered shell

* feat: add client-owned shell mouse controls

* feat: complete client-owned shell chrome

* feat: add client-owned shell settings and notifications

* feat: run client shell custom commands

* feat: render popup terminals in client shell

* feat: add client-owned scrollback and copy mode

* fix: preserve client worktree trust defaults

* feat: render startup diagnostics in client shell

* feat: render onboarding in client shell

* feat: render product announcements in client shell

* feat: render release notes in client shell

* feat: render mobile switcher in client shell

* feat: render kitty graphics in client shell

* fix: preserve client shell lifecycle coherence

* refactor: route client shell commands through endpoint connections

* refactor: make the client-rendered shell the default

* refactor: remove monolithic launch mode

* refactor: complete client-rendered shell cutover

* perf: retain client pane surface updates

* perf: scale retained pane surface updates

* perf: remove remote pane input latency

* test: make client shell checks platform-independent

* fix: prevent client timer starvation

* test: fix client shell platform gates

* test: accept retained surfaces in cross-area checks

* test: make client mode assertions platform-neutral

* fix: badge only outdated integrations

11 files changed, 8 insertions, 41 deletions

diff --git a/docs/next/website/src/content/docs/cli-reference.mdx b/docs/next/website/src/content/docs/cli-reference.mdx
index 189be5b0..85fb3dad 100644
--- a/docs/next/website/src/content/docs/cli-reference.mdx
+++ b/docs/next/website/src/content/docs/cli-reference.mdx
@@ -15,7 +15,6 @@ herdr --session work          # launch or attach to a named session
 herdr --remote workbox        # attach through SSH, using local keybindings
 herdr --remote workbox --remote-keybindings server
 herdr --remote workbox --handoff
-herdr --no-session            # single-process escape hatch
 herdr --default-config        # print default config
 herdr update                  # download and install from the configured channel
 herdr update --handoff        # opt into live handoff for supported running servers
diff --git a/docs/next/website/src/content/docs/how-to-work.mdx b/docs/next/website/src/content/docs/how-to-work.mdx
index 8d3ad081..6e74e59d 100644
--- a/docs/next/website/src/content/docs/how-to-work.mdx
+++ b/docs/next/website/src/content/docs/how-to-work.mdx
@@ -100,4 +100,4 @@ herdr --remote workbox
 
 Use `herdr` for local work. Use `ssh you@server` then `herdr` when you want Herdr to behave like tmux on that remote shell or when you are using a phone SSH client. Use `herdr --remote <host>` when you want a local thin client for a remote session, including local clipboard image paste bridging.
 
-For remote bootstrap details, named remote sessions, custom binaries, direct terminal attach, and `--no-session`, see [Persistence and remote access](/docs/persistence-remote/).
+For remote bootstrap details, named remote sessions, custom binaries, and direct terminal attach, see [Persistence and remote access](/docs/persistence-remote/).
diff --git a/docs/next/website/src/content/docs/ja/cli-reference.mdx b/docs/next/website/src/content/docs/ja/cli-reference.mdx
index 0b3e06f3..d443f317 100644
--- a/docs/next/website/src/content/docs/ja/cli-reference.mdx
+++ b/docs/next/website/src/content/docs/ja/cli-reference.mdx
@@ -15,7 +15,6 @@ herdr --session work          # 名前付きセッションを起動またはア
 herdr --remote workbox        # SSH 越しにアタッチ (ローカルのキーバインドを使用)
 herdr --remote workbox --remote-keybindings server
 herdr --remote workbox --handoff
-herdr --no-session            # シングルプロセスの逃げ道
 herdr --default-config        # デフォルト設定を表示
 herdr update                  # 設定済みチャンネルからダウンロードしてインストール
 herdr update --handoff        # 対応する実行中サーバーでライブハンドオフにオプトイン
diff --git a/docs/next/website/src/content/docs/ja/how-to-work.mdx b/docs/next/website/src/content/docs/ja/how-to-work.mdx
index 0365df0b..d6d6bd95 100644
--- a/docs/next/website/src/content/docs/ja/how-to-work.mdx
+++ b/docs/next/website/src/content/docs/ja/how-to-work.mdx
@@ -100,4 +100,4 @@ herdr --remote workbox
 
 ローカル作業には `herdr` を使います。リモートシェル上で Herdr を tmux のように使いたいときや、スマートフォンの SSH クライアントを使っているときは `ssh you@server` してから `herdr` を使います。リモートセッション用のローカルシンクライアントが欲しいとき (ローカルクリップボードの画像貼り付けブリッジを含む) は `herdr --remote <host>` を使います。
 
-リモートブートストラップの詳細、名前付きリモートセッション、カスタムバイナリ、ダイレクトターミナルアタッチ、`--no-session` については[永続化とリモートアクセス](/ja/docs/persistence-remote/)を参照してください。
+リモートブートストラップの詳細、名前付きリモートセッション、カスタムバイナリ、ダイレクトターミナルアタッチについては[永続化とリモートアクセス](/ja/docs/persistence-remote/)を参照してください。
diff --git a/docs/next/website/src/content/docs/ja/persistence-remote.mdx b/docs/next/website/src/content/docs/ja/persistence-remote.mdx
index 266d407b..23c6e817 100644
--- a/docs/next/website/src/content/docs/ja/persistence-remote.mdx
+++ b/docs/next/website/src/content/docs/ja/persistence-remote.mdx
@@ -118,13 +118,3 @@ herdr terminal attach term_abc123
 ```bash
 herdr terminal attach term_abc123 --takeover
 ```
-
-## シングルプロセスの逃げ道
-
-バックグラウンドのサーバー/クライアント分離なしで Herdr を実行するには `--no-session` を使います:
-
-```bash
-herdr --no-session
-```
-
-これは主にデバッグや互換性のための逃げ道です。デフォルトの永続セッションモードが通常の使い方です。
diff --git a/docs/next/website/src/content/docs/persistence-remote.mdx b/docs/next/website/src/content/docs/persistence-remote.mdx
index 5044c66d..bb8404c8 100644
--- a/docs/next/website/src/content/docs/persistence-remote.mdx
+++ b/docs/next/website/src/content/docs/persistence-remote.mdx
@@ -151,13 +151,3 @@ newline-delimited JSON commands on stdin. `terminal.input` sends text or
 base64 bytes, `terminal.resize` changes the controller viewport,
 `terminal.scroll` scrolls the attached viewport, and `terminal.release` closes
 the controller. Only one controller owns input and resize at a time.
-
-## Single-process escape hatch
-
-Use `--no-session` to run Herdr without the background server/client split:
-
-```bash
-herdr --no-session
-```
-
-Use `--no-session` mainly for debugging or compatibility. Persistent session mode remains the default.
diff --git a/docs/next/website/src/content/docs/socket-api.mdx b/docs/next/website/src/content/docs/socket-api.mdx
index 8a055a36..4d4559c1 100644
--- a/docs/next/website/src/content/docs/socket-api.mdx
+++ b/docs/next/website/src/content/docs/socket-api.mdx
@@ -191,8 +191,8 @@ layers are placed in stable `(z_index, layer_id)` order. Each stream exclusively
 closing it removes that layer. Inline frames accept `png`, `rgb`, `rgba`, or
 `bgra`; BGRA is normalized once to owned RGBA. Herdr advances the host cache
 one image transaction per render pass, so arbitrary layer sets progress without
-an aggregate frame. Headless transport keeps each transaction within its 32 MiB
-wire limit; local monolithic rendering does not apply that transport limit.
+an aggregate frame. Client transport keeps each transaction within its 32 MiB
+wire limit.
 
 ```json
 {"id":"graphics_info","method":"pane.graphics.info","params":{"pane_id":"w1:p1"}}
@@ -219,8 +219,8 @@ inline. Herdr replies with a `pane_graphics_frame_ack` only after the terminal
 accepts the file, or after a safe owned inline fallback is installed. Confirmed
 file-transport failure disables direct files for that client connection without
 disabling exact pixel mouse. A timeout or client loss closes the stream without
-acknowledging source reuse. Monolithic `--no-session` mode advertises neither
-fast file transport nor exact pixel mouse and remains on owned inline fallback.
+acknowledging source reuse. Clients that cannot negotiate direct file transport
+remain on the owned inline fallback.
 
 Direct files are always complete canonical `width * height * 4` RGBA frames.
 `file_frame_max_bytes` is the limit that remains eligible for owned inline fallback.
diff --git a/docs/next/website/src/content/docs/zh-cn/cli-reference.mdx b/docs/next/website/src/content/docs/zh-cn/cli-reference.mdx
index b00ad592..38a7a4f2 100644
--- a/docs/next/website/src/content/docs/zh-cn/cli-reference.mdx
+++ b/docs/next/website/src/content/docs/zh-cn/cli-reference.mdx
@@ -15,7 +15,6 @@ herdr --session work          # 启动或连接命名会话
 herdr --remote workbox        # 通过 SSH 连接,使用本地按键绑定
 herdr --remote workbox --remote-keybindings server
 herdr --remote workbox --handoff
-herdr --no-session            # 单进程逃生舱
 herdr --default-config        # 打印默认配置
 herdr update                  # 从配置的通道下载并安装
 herdr update --handoff        # 对受支持的运行中服务器启用实时交接
diff --git a/docs/next/website/src/content/docs/zh-cn/how-to-work.mdx b/docs/next/website/src/content/docs/zh-cn/how-to-work.mdx
index 0df1b87f..5f455a66 100644
--- a/docs/next/website/src/content/docs/zh-cn/how-to-work.mdx
+++ b/docs/next/website/src/content/docs/zh-cn/how-to-work.mdx
@@ -100,4 +100,4 @@ herdr --remote workbox
 
 本地工作用 `herdr`。想让 Herdr 在远程 shell 上表现得像 tmux,或者在用手机 SSH 客户端时,用 `ssh you@server` 再 `herdr`。想要一个连接远程会话的本地瘦客户端 (包括本地剪贴板图像粘贴桥接) 时,用 `herdr --remote <host>`。
 
-关于远程引导细节、命名远程会话、自定义二进制、直接终端附加和 `--no-session`,参见[持久化与远程访问](/zh-cn/docs/persistence-remote/)。
+关于远程引导细节、命名远程会话、自定义二进制和直接终端附加,参见[持久化与远程访问](/zh-cn/docs/persistence-remote/)。
diff --git a/docs/next/website/src/content/docs/zh-cn/persistence-remote.mdx b/docs/next/website/src/content/docs/zh-cn/persistence-remote.mdx
index ba50130e..3f142547 100644
--- a/docs/next/website/src/content/docs/zh-cn/persistence-remote.mdx
+++ b/docs/next/website/src/content/docs/zh-cn/persistence-remote.mdx
@@ -118,13 +118,3 @@ herdr terminal attach term_abc123
 ```bash
 herdr terminal attach term_abc123 --takeover
 ```
-
-## 单进程逃生舱
-
-用 `--no-session` 在没有后台服务器/客户端分离的情况下运行 Herdr:
-
-```bash
-herdr --no-session
-```
-
-这主要是调试或兼容性的逃生舱。默认的持久会话模式才是常规路径。
diff --git a/docs/next/website/src/data/config-reference.json b/docs/next/website/src/data/config-reference.json
index 475c6a07..db22daf1 100644
--- a/docs/next/website/src/data/config-reference.json
+++ b/docs/next/website/src/data/config-reference.json
@@ -575,7 +575,7 @@
           "key": "keys.detach",
           "type": "keybinding",
           "default": "\"prefix+q\"",
-          "description": "Detach from server/client mode, or exit --no-session mode."
+          "description": "Detach the current client from its Herdr server."
         },
         {
           "key": "keys.reload_config",