refactor(core): 统一模板引擎到 src/template/ 目录

- 将 agent/prompt-template/ 目录合并到 src/template/
- 新增通用模板函数 renderTemplate、render
- 新增 Agent 特定函数 renderPromptTemplate、renderPrompt
- 新增 createToolDescriptionContext 支持工具描述模板变量
- 支持 ${GREP_TOOL_NAME} 等 Claude Code 风格变量
- 更新所有相关导入路径

packages/core/tests/unit/agent/prompt-template.test.ts

@@ -1,11 +1,15 @@
 import { describe, it, expect, beforeEach } from 'vitest';
 import {
-  renderTemplate,
+  renderPromptTemplate,
   createDefaultContext,
   createPlanContext,
+  createToolDescriptionContext,
   DEFAULT_TOOL_NAMES,
-} from '../../../src/agent/prompt-template/index.js';
-import type { PromptContext } from '../../../src/agent/prompt-template/types.js';
+} from '../../../src/template/index.js';
+import type { PromptContext } from '../../../src/template/types.js';
+
+// Alias for backward compatibility in tests
+const renderTemplate = renderPromptTemplate;
 
 describe('Prompt Template System', () => {
   let context: PromptContext;
@@ -178,4 +182,74 @@ describe('Prompt Template System', () => {
       expect(result).toBe('primary');
     });
   });
+
+  describe('createToolDescriptionContext', () => {
+    it('should create context with uppercase tool name variables', () => {
+      const ctx = createToolDescriptionContext();
+      // Check that uppercase tool names are available in custom
+      expect(ctx.custom).toBeDefined();
+      expect(ctx.custom!['GLOB_TOOL_NAME']).toBe('glob');
+      expect(ctx.custom!['GREP_TOOL_NAME']).toBe('grep');
+      expect(ctx.custom!['BASH_TOOL_NAME']).toBe('bash');
+      expect(ctx.custom!['READ_TOOL_NAME']).toBe('read_file');
+      expect(ctx.custom!['WRITE_TOOL_NAME']).toBe('write_file');
+      expect(ctx.custom!['EDIT_TOOL_NAME']).toBe('edit_file');
+      expect(ctx.custom!['TASK_TOOL_NAME']).toBe('task');
+    });
+
+    it('should convert camelCase to UPPER_SNAKE_CASE correctly', () => {
+      const ctx = createToolDescriptionContext();
+      // askUserQuestion -> ASK_USER_QUESTION_TOOL_NAME
+      expect(ctx.custom!['ASK_USER_QUESTION_TOOL_NAME']).toBe('ask_user_question');
+      // exitPlanMode -> EXIT_PLAN_MODE_TOOL_NAME
+      expect(ctx.custom!['EXIT_PLAN_MODE_TOOL_NAME']).toBe('exit_plan_mode');
+      // webSearch -> WEB_SEARCH_TOOL_NAME
+      expect(ctx.custom!['WEB_SEARCH_TOOL_NAME']).toBe('web_search');
+    });
+
+    it('should support rendering with uppercase tool name variables', () => {
+      const ctx = createToolDescriptionContext();
+      const template = 'Use ${GREP_TOOL_NAME} for search. Never use ${BASH_TOOL_NAME} grep.';
+      const result = renderTemplate(template, ctx);
+      expect(result).toBe('Use grep for search. Never use bash grep.');
+    });
+
+    it('should support both lowercase and uppercase variable styles', () => {
+      const ctx = createToolDescriptionContext();
+      const template = 'Tools: ${tools.grep} or ${GREP_TOOL_NAME}';
+      const result = renderTemplate(template, ctx);
+      expect(result).toBe('Tools: grep or grep');
+    });
+
+    it('should preserve overrides', () => {
+      const ctx = createToolDescriptionContext({
+        agent: {
+          name: 'custom-agent',
+          mode: 'subagent',
+          isSubagent: true,
+        },
+      });
+      expect(ctx.agent.name).toBe('custom-agent');
+      expect(ctx.agent.mode).toBe('subagent');
+      expect(ctx.agent.isSubagent).toBe(true);
+      // Uppercase tool names should still be available
+      expect(ctx.custom!['GREP_TOOL_NAME']).toBe('grep');
+    });
+
+    it('should render Claude Code style tool description template', () => {
+      const ctx = createToolDescriptionContext();
+      // Example from Claude Code official prompt
+      const template = `A powerful search tool built on ripgrep
+
+Usage:
+- ALWAYS use \${GREP_TOOL_NAME} for search tasks. NEVER invoke \`grep\` or \`rg\` as a \${BASH_TOOL_NAME} command.
+- Use \${TASK_TOOL_NAME} tool for open-ended searches requiring multiple rounds`;
+
+      const result = renderTemplate(template, ctx);
+
+      expect(result).toContain('ALWAYS use grep for search tasks');
+      expect(result).toContain('NEVER invoke `grep` or `rg` as a bash command');
+      expect(result).toContain('Use task tool for open-ended searches');
+    });
+  });
 });