refactor: use ContextCollector for hook injection and remove unused background tools

Split changes:
- Replace injectHookMessage with ContextCollector.register() pattern for improved hook content injection
- Remove unused background task tools infrastructure (createBackgroundOutput, createBackgroundCancel)

🤖 Generated with assistance of OhMyOpenCode (https://github.com/code-yeongyu/oh-my-opencode)

src/hooks/claude-code-hooks/index.ts

@@ -27,14 +27,18 @@ import { cacheToolInput, getToolInput } from "./tool-input-cache"
 import { recordToolUse, recordToolResult, getTranscriptPath, recordUserMessage } from "./transcript"
 import type { PluginConfig } from "./types"
 import { log, isHookDisabled } from "../../shared"
-import { injectHookMessage } from "../../features/hook-message-injector"
 import { detectKeywordsWithType, removeCodeBlocks } from "../keyword-detector"
+import type { ContextCollector } from "../../features/context-injector"
 
 const sessionFirstMessageProcessed = new Set<string>()
 const sessionErrorState = new Map<string, { hasError: boolean; errorMessage?: string }>()
 const sessionInterruptState = new Map<string, { interrupted: boolean }>()
 
-export function createClaudeCodeHooksHook(ctx: PluginInput, config: PluginConfig = {}) {
+export function createClaudeCodeHooksHook(
+  ctx: PluginInput,
+  config: PluginConfig = {},
+  contextCollector?: ContextCollector
+) {
   return {
     "experimental.session.compacting": async (
       input: { sessionID: string },
@@ -164,24 +168,26 @@ export function createClaudeCodeHooksHook(ctx: PluginInput, config: PluginConfig
               output.parts[idx].text = `${hookContent}\n\n${output.parts[idx].text ?? ""}`
               log("UserPromptSubmit hooks prepended to first message parts directly", { sessionID: input.sessionID })
             }
-          } else {
+          } else if (contextCollector) {
-            const message = output.message as {
+            contextCollector.register(input.sessionID, {
-              agent?: string
+              id: "hook-context",
-              model?: { modelID?: string; providerID?: string }
+              source: "custom",
-              path?: { cwd?: string; root?: string }
+              content: hookContent,
-              tools?: Record<string, boolean>
+              priority: "high",
-            }
-
-            const success = injectHookMessage(input.sessionID, hookContent, {
-              agent: message.agent,
-              model: message.model,
-              path: message.path ?? { cwd: ctx.directory, root: "/" },
-              tools: message.tools,
             })
 
-            log(success ? "Hook message injected via file system" : "File injection failed", {
+            log("Hook content registered for synthetic message injection", {
               sessionID: input.sessionID,
+              contentLength: hookContent.length,
             })
+          } else {
+            const idx = output.parts.findIndex((p) => p.type === "text" && p.text)
+            if (idx >= 0) {
+              output.parts[idx].text = `${hookContent}\n\n${output.parts[idx].text ?? ""}`
+              log("Hook content prepended to message (fallback)", {
+                sessionID: input.sessionID,
+              })
+            }
           }
         }
       }

src/index.ts

@@ -126,10 +126,14 @@ const OhMyOpenCodePlugin: Plugin = async (ctx) => {
     ? createEmptyTaskResponseDetectorHook(ctx)
     : null;
   const thinkMode = isHookEnabled("think-mode") ? createThinkModeHook() : null;
-  const claudeCodeHooks = createClaudeCodeHooksHook(ctx, {
+  const claudeCodeHooks = createClaudeCodeHooksHook(
-    disabledHooks: (pluginConfig.claude_code?.hooks ?? true) ? undefined : true,
+    ctx,
-    keywordDetectorDisabled: !isHookEnabled("keyword-detector"),
+    {
-  });
+      disabledHooks: (pluginConfig.claude_code?.hooks ?? true) ? undefined : true,
+      keywordDetectorDisabled: !isHookEnabled("keyword-detector"),
+    },
+    contextCollector
+  );
   const anthropicContextWindowLimitRecovery = isHookEnabled(
     "anthropic-context-window-limit-recovery"
   )
@@ -224,7 +228,7 @@ const OhMyOpenCodePlugin: Plugin = async (ctx) => {
   const backgroundNotificationHook = isHookEnabled("background-notification")
     ? createBackgroundNotificationHook(backgroundManager)
     : null;
-  const backgroundTools = createBackgroundTools(backgroundManager, ctx.client);
+  const backgroundTools = createBackgroundTools();
 
   const callOmoAgent = createCallOmoAgent(ctx, backgroundManager);
   const lookAt = createLookAt(ctx);

src/tools/index.ts

@@ -35,25 +35,14 @@ export { createSkillTool } from "./skill"
 export { getTmuxPath } from "./interactive-bash/utils"
 export { createSkillMcpTool } from "./skill-mcp"
 
-import {
+import type { ToolDefinition } from "@opencode-ai/plugin"
-  createBackgroundOutput,
-  createBackgroundCancel,
-} from "./background-task"
-
-import type { PluginInput, ToolDefinition } from "@opencode-ai/plugin"
-import type { BackgroundManager } from "../features/background-agent"
-
-type OpencodeClient = PluginInput["client"]
 
 export { createCallOmoAgent } from "./call-omo-agent"
 export { createLookAt } from "./look-at"
 export { createSisyphusTask, type SisyphusTaskToolOptions, DEFAULT_CATEGORIES, CATEGORY_PROMPT_APPENDS } from "./sisyphus-task"
 
-export function createBackgroundTools(manager: BackgroundManager, client: OpencodeClient): Record<string, ToolDefinition> {
+export function createBackgroundTools(): Record<string, ToolDefinition> {
-  return {
+  return {}
-    background_output: createBackgroundOutput(manager, client),
-    background_cancel: createBackgroundCancel(manager, client),
-  }
 }
 
 export const builtinTools: Record<string, ToolDefinition> = {