[FEATURE]: Add opencode-quota to ecosystem plugins #24878

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Describe the enhancement you want to request

Describe the enhancement

Add opencode-quota to the Plugins table on the ecosystem docs page.

opencode-quota provides provider quota toasts and local token usage reports without making LLM/model API calls. Listing it in the ecosystem docs would make it easier for users to discover a plugin focused on quota visibility and local usage reporting. Works via toasts, TUI sidebar, and slash commands.

Proposed docs change

Add this plugin entry to packages/web/src/content/docs/ecosystem.mdx:

• Plugin: opencode-quota
• URL: https://github.com/slkiser/opencode-quota
• Description: Provider quota toasts and local token usage reports with zero LLM/model API calls

Related PR

Implemented in #21905.