feat: complete custom agent support for ALL remaining IDEs

## Added installCustomAgentLauncher to remaining IDEs:

✅ Qwen (.qwen/commands/BMad/)
- TOML format with proper description and prompt fields
- Uses existing processAgentLauncherContent method
- Format: custom-{agent-name}.toml

✅ Trae (.trae/rules/)
- Markdown format with bmad-agent-custom- prefix
- Follows existing BMAD naming pattern
- Format: bmad-agent-custom-{agent-name}.md

✅ Roo (.roomodes)
- YAML format appends to existing customModes section
- Creates customModes section if missing
- Format: bmad-custom-{agent-name} (slug-based)

✅ Kilo (.kilocodemodes)
- YAML format identical to Roo pattern
- Handles existing customModes gracefully
- Format: bmad-custom-{agent-name} (slug-based)

✅ Auggie (.augment/commands/bmad/)
- Frontmatter + Markdown format
- Follows existing Auggie command pattern
- Format: custom-{agent-name}.md

## Complete IDE Coverage:
ALL IDEs now support custom agent installation:
- 16 total IDEs with custom agent support
- Various formats: TOML, YAML, Markdown, file-based
- All include @agentPath references and usage instructions
- Proper IDE-specific naming and directory structures

Custom agents from .bmad/custom/src/agents/ now install to EVERY configured IDE!

tools/cli/installers/lib/ide/trae.js

@@ -261,6 +261,52 @@ Part of the BMAD ${workflow.module.toUpperCase()} module.
       }
     }
   }
+
+  /**
+   * Install a custom agent launcher for Trae
+   * @param {string} projectDir - Project directory
+   * @param {string} agentName - Agent name (e.g., "fred-commit-poet")
+   * @param {string} agentPath - Path to compiled agent (relative to project root)
+   * @param {Object} metadata - Agent metadata
+   * @returns {Object} Installation result
+   */
+  async installCustomAgentLauncher(projectDir, agentName, agentPath, metadata) {
+    const traeDir = path.join(projectDir, this.configDir);
+    const rulesDir = path.join(traeDir, this.rulesDir);
+
+    // Create .trae/rules directory if it doesn't exist
+    await fs.ensureDir(rulesDir);
+
+    // Create custom agent launcher
+    const launcherContent = `# ${agentName} Custom Agent
+
+**⚠️ IMPORTANT**: Run @${agentPath} first to load the complete agent!
+
+This is a launcher for the custom BMAD agent "${agentName}".
+
+## Usage
+1. First run: \`${agentPath}\` to load the complete agent
+2. Then use this rule to activate ${agentName}
+
+The agent will follow the persona and instructions from the main agent file.
+
+---
+
+*Generated by BMAD Method*`;
+
+    const fileName = `bmad-agent-custom-${agentName.toLowerCase()}.md`;
+    const launcherPath = path.join(rulesDir, fileName);
+
+    // Write the launcher file
+    await fs.writeFile(launcherPath, launcherContent, 'utf8');
+
+    return {
+      ide: 'trae',
+      path: path.relative(projectDir, launcherPath),
+      command: agentName,
+      type: 'custom-agent-launcher',
+    };
+  }
 }
 
 module.exports = { TraeSetup };