Replace Coder with Code Geek

[angnuoli]

Summary

• replace the Coder market template with Code Geek while preserving the compatible coder runtime ID
• add a dedicated Code Geek workspace persona with SOUL.md, AGENTS.md, and IDENTITY.md
• update English and Chinese market copy, tags, and quick tasks for app prototyping, code audits, and build diagnostics
• cover the catalog, persona seeding, and renderer presentation with targeted tests

Validation

• cd desktop && npx vitest run src/agent-catalog.test.ts src/agent-personas.test.ts
• cd desktop/renderer && npx vitest run src/stores/agents.test.ts src/views/AgentMarketView.test.ts
• cd desktop && npm run build

Progresses #129.