browser/openspec/changes/implement-plugin-marketplace-api-driven-ui/proposal.md

Why

The plugin registry and bridge contracts exist, but the plugin marketplace page still needs to be driven by platform API data instead of hardcoded catalog state. Operators need to browse installed game management plugins, inspect manifest-backed capabilities, and start install/enable workflows without exposing host paths, run sockets, credentials, or raw AI provider keys.

What Changes

• Add marketplace-focused API responses derived from installed game plugin registry metadata.
• Add platform service and handler behavior for listing marketplace plugins, viewing detail, and changing install/enable state through safe metadata workflows.
• Replace production hardcoded marketplace data in platform_web with API client calls, typed contracts, loading/error states, filters, and plugin detail/install actions.
• Preserve the magical-girl crystal-moonlight console visual direction while keeping the marketplace operational and game-management focused.
• Add backend, frontend, browser walkthrough, structure, and strict OpenSpec verification.

Capabilities

New Capabilities

• plugin-marketplace-api-driven-ui: Platform and frontend workflows for rendering the plugin marketplace from registry APIs and managing installed plugin state safely.

Modified Capabilities

• Builds on plugin-registry-and-manifest-validation and plugin-bridge-and-sdk; it does not change their archived contracts directly.

Impact

• Affects platform/ game plugin DTOs, service, validators, API routes, and docs.
• Affects platform_web/ API types/client methods, plugin marketplace page/components, and tests.
• Does not add billing, cloud host sales, provider marketplaces, unrelated SaaS marketplace behavior, direct plugin-run access, or raw key exposure.