fix: 主线 A 事件落库地基 + 主线 B1/B2 执行原语

主线 A（事件驱动落库）:
- 统一 EventStore 模块单例：RuntimeApp 不再 new EventStore，改用 eventStore
  并 setRepositories(14 个 domain repo),消除事件流向空 DB 的割裂
- Scheduler.create_tasks 改为 async,真正发出 task.created 事件
- run.ts dispatchTask 加 await
- 主线 A 独立复审发现并修复关键假绿：四个 repo（Task/Agent/ToolRun/
  TaskAttempt）的 *Update 类型 Omit<'status'> 且 update() 主动丢弃 status,
  导致 EventStore.project() 的状态写入全部静默失效,DB 行内容 tasks.status
  永远冻结在 pending,UI 显示的 completed 来自内存 graph。已修,DB 现
  真实反映 task.status=completed
- 补 agent.started/agent.completed/agent.failed 事件发出（之前 agents 表
  恒空),修复后 agents 表有正确行+status

主线 B1（结构化工具调用块类型,N1）:
- 新增 content-block.ts 定义 Anthropic canonical content blocks
  (TextBlock/ThinkingBlock/ToolUseBlock/ToolResultBlock/CanonicalMessage)
- provider.ts ProviderCompletionInput 去掉 unknown 逃生舱:
  messages: CanonicalMessage[], tools?: ToolDefinitionBlock[],
  tool_choice?: ToolChoice, system?: string | TextBlock[]

主线 B2（read-before-edit 代码层强制,FR-009）:
- fs/index.ts 新增 readFileState 机制(移植 claude-code FileEditTool),
  fs.edit 执行前检查:未读先改报 "File has not been read yet",外部修改
  报 "File has been unexpectedly modified"
- 修复 fs.edit 参数名不匹配:兼容 old_str/new_str (ExecutorRole) 和
  find/replace (UI) 两种命名
- fs_edit 唯一性检查(非 global 模式下 old_str 出现多次报错)

真实验收:
- TSC=0
- air run 后 DB:events=5(原 3,+agent.started/completed),
  tasks.status=completed(原 frozen pending),agents 1 行 status=completed
- read-before-edit 行为测试:未读先改 status=error,读后再改 status=ok

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/contracts/src/content-block.ts

@@ -0,0 +1,74 @@
+/**
+ * Anthropic canonical content block types
+ * Per constraint #6: Anthropic canonical content blocks
+ *
+ * @module packages/contracts/src/content-block
+ */
+
+/**
+ * Text content block
+ */
+export interface TextBlock {
+  type: 'text'
+  text: string
+}
+
+/**
+ * Thinking/reasoning block (for models that support it)
+ */
+export interface ThinkingBlock {
+  type: 'thinking'
+  thinking: string
+}
+
+/**
+ * Tool use block - represents a tool call request
+ */
+export interface ToolUseBlock {
+  type: 'tool_use'
+  id: string
+  name: string
+  input: Record<string, unknown>
+}
+
+/**
+ * Tool result block - represents the result of a tool execution
+ */
+export interface ToolResultBlock {
+  type: 'tool_result'
+  tool_use_id: string
+  content: string | ContentBlock[]
+  is_error?: boolean
+}
+
+/**
+ * Union of all canonical content block types
+ */
+export type ContentBlock = TextBlock | ThinkingBlock | ToolUseBlock | ToolResultBlock
+
+/**
+ * Canonical message format using content blocks
+ */
+export interface CanonicalMessage {
+  role: 'user' | 'assistant' | 'system'
+  content: string | ContentBlock[]
+  // Optional thinking for assistant messages
+  thinking?: string
+}
+
+/**
+ * Tool definition for tool use blocks
+ */
+export interface ToolDefinitionBlock {
+  name: string
+  description: string
+  input_schema: Record<string, unknown>
+}
+
+/**
+ * Tool choice specification
+ */
+export type ToolChoice =
+  | { type: 'auto' }
+  | { type: 'any' }
+  | { type: 'tool'; name: string }

packages/contracts/src/index.ts

@@ -4,6 +4,7 @@
 export * from './ids'           // §2 Core Primitive Types
 export * from './error'         // §3 Error Contracts
 export * from './event'         // §5 Runtime Event Contracts
+export * from './content-block' // §6 Anthropic Canonical Content Blocks
 export * from './runtime'       // §10 Worker/IPC Contracts (runtime context)
 export * from './ipc'           // §10 Worker/IPC Contracts
 export * from './task'          // §9 Task and Scheduler Contracts
@@ -11,7 +12,7 @@ export * from './worker-result' // §11 WorkerResult Contracts
 export * from './tool'          // §12 Tool Contracts + §21 Diagnostic Contracts
 export * from './permission'    // §13 Permission Contracts
 export * from './artifact'      // §14 Artifact Contracts
-export * from './evidence'      // §14 Evidence Contracts
+export * from './evidence'      // <EFBFBD><EFBFBD>14 Evidence Contracts
 export * from './project'       // §8 Project and Session Contracts
 
 // Provider exports - re-export with disambiguation for duplicate names

packages/contracts/src/provider.ts

@@ -13,6 +13,14 @@ import type {
   JsonObject,
 } from './ids'
 
+// Import content block types for canonical message format
+import type {
+  CanonicalMessage,
+  TextBlock,
+  ToolDefinitionBlock,
+  ToolChoice,
+} from './content-block'
+
 // =============================================================================
 // §15 — Provider Contracts
 // =============================================================================
@@ -180,10 +188,10 @@ export interface ProviderCompletionInput {
   provider_id: ProviderID
   model_id: ModelID
   canonical_format: 'anthropic'
-  messages: unknown[]
-  tools?: unknown[]
-  tool_choice?: unknown
-  system?: unknown
+  messages: CanonicalMessage[]
+  tools?: ToolDefinitionBlock[]
+  tool_choice?: ToolChoice
+  system?: string | TextBlock[]
   max_output_tokens?: number
   temperature?: number
   metadata?: JsonObject