feat: 新增第 8 个内置 tab「文件追踪」——移植 dsh-file-trace 插件

- 数据层：直接折叠会话事件日志(tool/call + tool/result 对)提取文件操作，
  与仓库「读事件日志而非动注册表」的取向一致；含错误文本捕获与
  running 态实时更新(ctx.on('session/event')，不可见时暂停、恢复时追平)
- 视图：操作列表 + 底部可拖拽 diff 面板；行级 diff(删红/增绿/改蓝)+
  行内字符级高亮；读取视图带真实行号；失败操作统一展示真实错误文本
- 语法着色：轻量分词器(关键字/字符串/数字/类型/函数/注释/预处理)，
  色相经 color-mix 落在 diff 三色之间的空档；跨行块注释状态按行序推导
- 单实例 tab，+ 菜单 order 55，角标显示操作数；设置页可整体关闭
  (与独立维护的 dsh-file-trace 插件共存)
- i18n：10 个新 key 同步全部 21 个词典；builtins 测试 7→8；
  README/指南内置清单同步

tests/builtins.spec.ts

@@ -1,5 +1,5 @@
 /**
- * Built-in registration tests: the plugin registers 7 tabs and 6 file
+ * Built-in registration tests: the plugin registers 8 tabs and 6 file
  * viewers through the same service external plugins use (dogfooding);
  * the catch-all `code` viewer, the NUL-sniffing `binary-download` viewer,
  * and the html sandbox settings pin the registry's behavior. (Office
@@ -27,13 +27,22 @@ function setup(options: BuiltinTabOptions = {}): { service: ReturnType<typeof cr
 }
 
 describe('built-in tab registrations', () => {
-  it('registers the 7 built-in tabs', () => {
+  it('registers the 8 built-in tabs', () => {
     const { service } = setup()
     expect(service.getTabs().map(t => t.id).sort()).toEqual(
-      ['browser', 'diff', 'editor', 'git', 'sidechat', 'subagent', 'terminal'],
+      ['browser', 'diff', 'editor', 'file-trace', 'git', 'sidechat', 'subagent', 'terminal'],
     )
   })
 
+  it('the file-trace tab is a single-instance badge-carrying visible tab', () => {
+    const { service } = setup()
+    const trace = service.getTab('file-trace')
+    expect(trace?.single).toBe(true)
+    expect(trace?.hidden).not.toBe(true)
+    expect(trace?.badge).toBeDefined()
+    expect(trace?.component).toBeDefined()
+  })
+
   it('only diff is hidden from the + menu; editor is the visible files window (order 10)', () => {
     const { service } = setup()
     expect(service.getTabs().filter(t => t.hidden).map(t => t.id)).toEqual(['diff'])

tests/filetrace.spec.ts

@@ -0,0 +1,126 @@
+/**
+ * File-trace tab data layer: event-log folding into file operations, plus a
+ * sanity pass over the ported diff/highlight engines (their full behavior
+ * suites live in the standalone dsh-file-trace plugin).
+ */
+import { describe, expect, it } from 'vitest'
+import { extractFileOps, groupByFile, knownContentBefore, parseReadLines } from '../src/client/filetrace/ops.ts'
+import { diffLines, buildDiffSegments, coalesceInline, diffInline } from '../src/client/filetrace/diff.ts'
+import { langOfPath, scanLine } from '../src/client/filetrace/highlight.ts'
+import type { SidebarSessionEvent } from '../src/context-types.ts'
+
+/** One synthetic session event. */
+function ev(type: string, seq: number, time: number, data: Record<string, unknown>): SidebarSessionEvent {
+  return { type, seq, time, data }
+}
+
+/** A tool/call event. */
+function call(seq: number, name: string, callId: string, args: unknown, time = seq): SidebarSessionEvent {
+  return ev('tool/call', seq, time, { name, callId, arguments: JSON.stringify(args) })
+}
+
+/** A tool/result event carrying one tool-result block with inner text. */
+function result(seq: number, callId: string, text: string, isError = false, time = seq): SidebarSessionEvent {
+  return ev('tool/result', seq, time, {
+    message: {
+      source: { kind: 'tool', callId },
+      content: [{ type: 'tool-result', isError, content: [{ type: 'text', text }] }],
+    },
+  })
+}
+
+describe('extractFileOps', () => {
+  it('seeds running ops from tool/call and settles them from tool/result', () => {
+    const ops = extractFileOps([
+      call(1, 'write', 'w1', { file_path: 'a.ts', content: 'body' }),
+      result(2, 'w1', '<path>a.ts</path>\n<type>file</type>\n<content>\nbody\n</content>'),
+    ])
+    expect(ops).toHaveLength(1)
+    expect(ops[0]!.running).toBe(false)
+    expect(ops[0]!.isError).toBe(false)
+    expect(ops[0]!.content).toBe('body')
+  })
+
+  it('captures the error text of an errored result for every kind', () => {
+    const ops = extractFileOps([
+      call(1, 'write', 'w', { file_path: 'a', content: 'x' }),
+      result(2, 'w', '写入失败：目标只读', true),
+      call(3, 'read', 'r', { file_path: 'b' }),
+      result(4, 'r', 'cannot read "b": not found', true),
+    ])
+    expect(ops.every(op => op.isError && op.errorText !== undefined)).toBe(true)
+    expect(ops.find(op => op.kind === 'read')?.errorText).toBe('cannot read "b": not found')
+  })
+
+  it('keeps a call without result as running, and reads capture their content', () => {
+    const ops = extractFileOps([
+      call(1, 'read', 'r1', { file_path: 'a.ts' }),
+      result(2, 'r1', '<path>a.ts</path>\n<type>file</type>\n<content>\n1: hello\n\n(End of file - total 1 lines)\n</content>'),
+      call(3, 'edit', 'e1', { file_path: 'c.ts', old_string: 'x', new_string: 'y' }),
+    ])
+    const read = ops.find(op => op.callId === 'r1')
+    expect(read?.running).toBe(false)
+    expect(read?.read).toContain('1: hello')
+    const edit = ops.find(op => op.callId === 'e1')
+    expect(edit?.running).toBe(true)
+    expect(edit?.edit).toEqual({ oldString: 'x', newString: 'y' })
+  })
+
+  it('ignores non-file tools and unrelated results, newest first', () => {
+    const ops = extractFileOps([
+      call(1, 'pwsh', 'p', { command: 'ls' }),
+      result(2, 'unknown-call', 'orphan'),
+      call(3, 'read', 'r', { file_path: 'z.ts' }),
+    ])
+    expect(ops.map(op => op.callId)).toEqual(['r'])
+  })
+
+  it('groups by file newest-first and recovers prior write content', () => {
+    const ops = extractFileOps([
+      call(1, 'write', 'w1', { file_path: 'a.ts', content: 'first' }),
+      call(2, 'write', 'w2', { file_path: 'a.ts', content: 'second' }),
+      call(3, 'write', 'w3', { file_path: 'b.ts', content: 'x' }),
+    ])
+    expect([...groupByFile(ops).keys()]).toEqual(['b.ts', 'a.ts'])
+    expect(knownContentBefore(ops, 'a.ts', ops.find(op => op.callId === 'w2')!)).toBe('first')
+  })
+})
+
+describe('parseReadLines', () => {
+  it('recovers real line numbers from the read envelope', () => {
+    const lines = parseReadLines('<path>a.ts</path>\n<type>file</type>\n<content>\n10: x\n11: y\n\n(Showing lines 10-11 of 20. Use offset=12 to continue.)\n</content>')
+    expect(lines).toEqual([{ line: 10, text: 'x' }, { line: 11, text: 'y' }])
+  })
+})
+
+describe('ported diff/highlight engines (sanity)', () => {
+  it('diffLines pairs a rewrite as mod and folds context into hunks', () => {
+    const rows = diffLines('hello world', 'hello dsh')
+    expect(rows.map(r => r.kind)).toEqual(['mod', 'mod'])
+    const before = Array.from({ length: 6 }, (_, i) => ({ kind: 'context' as const, oldLine: i + 1, newLine: i + 1, text: 'c' + String(i) }))
+    const change = [{ kind: 'mod' as const, oldLine: 7, newLine: 7, text: 'X' }]
+    const after = Array.from({ length: 8 }, (_, i) => ({ kind: 'context' as const, oldLine: i + 8, newLine: i + 8, text: 'c' + String(i + 8) }))
+    const segments = buildDiffSegments([...before, ...change, ...after], 3)
+    expect(segments.map(s => s.kind)).toEqual(['fold', 'hunk', 'fold'])
+  })
+
+  it('coalesces the ported prefix/suffix inline diff into runs', () => {
+    const { old: oldSide } = diffInline('hello world', 'hello dsh')
+    expect(coalesceInline(oldSide)).toEqual([
+      { text: 'hello ', changed: false },
+      { text: 'world', changed: true },
+    ])
+  })
+
+  it('highlights keywords and threads block-comment state', () => {
+    expect(langOfPath('a.cpp')).toBe('cpp')
+    const open = scanLine('/* header', 'cpp')
+    expect(open.inBlock).toBe(true)
+    const mid = scanLine(' * interior note', 'cpp', true)
+    expect(mid.tokens).toEqual([{ text: ' * interior note', type: 'comment' }])
+    const code = scanLine('int main() { return 42; } // done', 'cpp')
+    expect(code.tokens).toContainEqual({ text: 'int', type: 'keyword' })
+    expect(code.tokens).toContainEqual({ text: '42', type: 'number' })
+    expect(code.tokens).toContainEqual({ text: '// done', type: 'comment' })
+  })
+})