Refactor project name from "Open Claude Design" to "Open Design" (#1)

* Refactor project name from "Open Claude Design" to "Open Design"

- Updated project name in package.json, package-lock.json, and README files.
- Changed CLI commands and references from "ocd" to "od".
- Adjusted file structure references in documentation and code to reflect new naming conventions.
- Enhanced .gitignore to include new runtime data files.
- Updated metadata in LICENSE file to match new project name.

* Add contributing guidelines in English and Chinese

- Introduced CONTRIBUTING.md and CONTRIBUTING.zh-CN.md to provide clear instructions for contributors.
- Outlined contribution types, local setup instructions, and merging criteria for skills and design systems.
- Enhanced README files to reference the new contributing guidelines.

src/i18n/locales/en.ts

@@ -37,13 +37,13 @@ export const en: Dict = {
   'common.daysShort': '{n}d',
   'common.untitled': 'Untitled',
 
-  'app.brand': 'Open Claude Design',
+  'app.brand': 'Open Design',
   'app.brandPill': 'Research Preview',
   'app.brandSubtitle': 'by Nexu Labs',
   'app.welcomeLoading': 'Loading workspace…',
 
   'settings.welcomeKicker': 'Welcome',
-  'settings.welcomeTitle': 'Set up Open Claude Design',
+  'settings.welcomeTitle': 'Set up Open Design',
   'settings.welcomeSubtitle':
     "Pick how you'd like to run generations. You can change this any time from the Settings button in the top bar.",
   'settings.kicker': 'Settings',