refactor(web): source the search result bound from its protocol constant

`ConnectionHandle.sessionSearchResultLimit` mirrored
`SESSION_SEARCH_RESULT_LIMIT` as per-connection state, giving one fact two
homes in the same module and implying a transport-varying or server-negotiated
bound that the response schema's fixed `max` forbids. `SessionsService` now
reads the constant directly and its constructor drops the parameter; the
connection handle and its unreachable `/client` value re-export go away.

The import comes from the inline-safe wire layer rather than the connection
plugin's `/client` surface, which the bundle-purity gate rejects for value
imports.

.agents/notes/implemented/feature/2026-07-27-web-session-search.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write .agents/notes/implemented/feature/2026-07-27-web-session-search.md
-2026-07-27-web-session-search.md: 3dd042056d97dd5d70bdb8c196b8356bae703a22
-2026-07-27-web-session-search.zh.md: 1600044ce15bd773f7bd21872ebdb13a9fd71d64
+2026-07-27-web-session-search.md: 7d7bcb84877b60d937de12afdb55925042992efb
+2026-07-27-web-session-search.zh.md: 54ab7e86ebd76061c94856462d22447c038edaf4

.agents/notes/implemented/feature/2026-07-27-web-session-search.md

@@ -16,6 +16,8 @@ The host gateway exposes `session.search` through the existing typed RPC stack.
 
 [`WorkspaceBrowser`](../../../../packages/client/ui-workspace/README.md) keeps metadata and content search deliberately separate. Its default copy is English, and its input plus defensive request path remove NUL and cap queries at the request schema's 500 UTF-16 code units without splitting a surrogate pair. A non-blank query immediately computes case-insensitive title and Workspace substring matches from the Session list, starts a 250 ms debounced content request, aborts the preceding request when the query changes, and ignores stale completions. It merges local matches first in recency order with backend-ranked content-only matches, deduplicates by session id, and renders a flat list regardless of the normal grouping mode. Each row shows the title, Workspace, and an available one-line snippet. Selecting a row opens the Session only and preserves the query; it does not navigate to an exact event.
 
+The result bound is one protocol constant, not per-connection state. `SESSION_SEARCH_RESULT_LIMIT` lives beside the response schema that enforces it in `dsh-host-apiproxy`, and `SessionsService.searchResultLimit` re-exposes that constant for presentation plugins. The connection handle does not carry it: a per-connection field would imply a transport-varying or server-negotiated bound that the schema's fixed `max` forbids, and would leave the same fact with two homes in the same module.
+
 Content matching inherits the SQLite backend's normalized literal token/phrase semantics. The shared semantic projection excludes reasoning blocks, so UI search never returns a model's private reasoning as a hit or snippet; the derived-index schema version advances so existing persistent indexes rebuild without the former documents. FTS5 operators are inert data, and this surface adds no typo, fuzzy, prefix, or arbitrary-substring expansion. In particular, the `unicode61` tokenizer may treat an uninterrupted Chinese sequence as one token, so a shorter query such as `搜索` is not guaranteed to match inside `会话搜索功能`. Title and Workspace matching remains ordinary client-side substring matching.
 
 ## Failure and visibility contract

.agents/notes/implemented/feature/2026-07-27-web-session-search.zh.md

@@ -16,6 +16,8 @@ Web 与 headless 共用的组合会使用 `openAt: first-search` 和内存数据
 
 [`WorkspaceBrowser`](../../../../packages/client/ui-workspace/README.md) 有意将元数据搜索与内容搜索保持独立。其默认界面文案为英文；输入框及防御性请求路径会移除 NUL，将查询限制在请求 schema 规定的 500 个 UTF-16 code unit 内且不会拆分 surrogate pair。非空白查询会立即从会话列表中计算不区分大小写的标题和 Workspace 子串匹配，在 250 ms 防抖后发起内容请求，在查询变化时中止前一请求，并忽略陈旧的完成结果。它先按新近程度排列本地匹配，再合并由后端排序且仅匹配内容的结果，按会话 id 去重；无论常规分组模式如何，最终都渲染为扁平列表。每一行显示标题、Workspace，并在存在时显示一行摘要片段。选择某一行只会打开对应会话，并保留查询条件；不会跳转至确切事件。
 
+结果上限是单一协议常量，而非逐连接状态。`SESSION_SEARCH_RESULT_LIMIT` 位于 `dsh-host-apiproxy` 中强制执行它的响应 schema 旁边，`SessionsService.searchResultLimit` 则把该常量重新公开给呈现插件。连接 handle 不携带它：逐连接字段会暗示该上限随传输层变化或由服务端协商，而 schema 固定的 `max` 恰恰禁止这一点，并且会让同一事实在同一模块内拥有两处归属。
+
 内容匹配沿用 SQLite 后端经过规范化的字面 token／短语语义。共享语义投影会排除推理（reasoning）块，因此 UI 搜索绝不会将模型的私有推理作为命中或 snippet 返回；派生索引的 schema 版本会随之前进，使现有持久化索引重建并移除先前的这些文档。FTS5 运算符只作为数据处理，此搜索界面不提供拼写错误纠正、模糊匹配、前缀匹配或任意子串扩展。特别是，`unicode61` 分词器可能将一段连续中文视作单个 token，因此不保证 `搜索` 之类的较短查询能匹配 `会话搜索功能` 的内部片段。标题与 Workspace 匹配仍采用普通的客户端子串匹配。
 
 ## 故障与可见性契约