story-kit: create 193_story_clickable_code_references_in_frontend

.story_kit/work/1_upcoming/193_story_clickable_code_references_in_frontend.md

@@ -8,6 +8,8 @@ name: "Clickable code references in frontend"
 
 As a developer using the Story Kit web UI, I want code references (e.g. `file_path:line_number`) to be rendered as clickable links that open the file in my local editor, so that I can quickly navigate to the relevant source code.
 
+Instead of using editor-specific URI schemes (vscode://, zed://, etc.), use a backend API endpoint to open files. The frontend sends a request like `POST /api/open-file?path=src/foo.rs&line=42` and the server invokes the configured editor CLI (e.g. `zed src/foo.rs:42`). This leverages the existing editor preference already used by the `get_editor_command` MCP tool, so changing the editor in one place works everywhere.
+
 ## Acceptance Criteria
 
 - [ ] Code references in the format `path/to/file.rs:123` are detected and rendered as clickable links in the frontend