feat(plugins): surface ep.json disables in plugin card (#395)

Plugins that intentionally remove a baseline Etherpad feature
(ep_disable_chat, ep_disable_change_author_name, etc.) declare which
features they disable in their ep.json `disables` array — see the
contract proposal at ether/etherpad#7648.

Render that list in the plugin card with an amber note ("Disables: chat")
so users see what they're losing before they install. The badge is
gated on `disables` being present and non-empty, so plugins without
a disables field render unchanged.

Note: this UI change is safe to ship now even before the
plugins.viewer.json build pipeline is updated to source `disables`
from ep.json — when the field is absent the badge no-ops.

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: JohnMcLear

src/components/Plugin.tsx

@@ -78,6 +78,17 @@ export const PluginCom: FC<PluginProps> = ({plugins}) => {
             </div>
         </div>
         <div>{plugins.description}</div>
+        {plugins.disables && plugins.disables.length > 0 && (
+            <div
+                className="mt-2 px-3 py-2 rounded-md text-sm bg-amber-950/50 border border-amber-800/60 text-amber-200"
+                title="This plugin intentionally removes the listed Etherpad features. See doc/PLUGIN_FEATURE_DISABLES.md."
+            >
+                <span className="font-semibold">Disables: </span>
+                {plugins.disables
+                    .map((tag) => tag.replace(/^@feature:/, ''))
+                    .join(', ')}
+            </div>
+        )}
         <div className="flex gap-10">
             {plugins.images && plugins.images.map((img, i) => <img src={img} className="w-60 object-contain" key={plugins.name + i} alt={"Image of " + plugins.name}/>)}
             {plugins.readme && <div className="w-full line-clamp-5 readme-of-plugin"

src/store/Plugin.ts

@@ -47,7 +47,23 @@ export type PluginResponseVal = {
         email: string
     },
     compatibility?: CompatibilityStatus,
-    images?: string[]
+    images?: string[],
+    /**
+     * `@feature:*` Playwright tags for core specs that the plugin
+     * intentionally disables. Sourced from the plugin's `ep.json`
+     * `disables` array; see ether/etherpad-lite#7648 and
+     * `doc/PLUGIN_FEATURE_DISABLES.md` for the contract.
+     *
+     * If present and non-empty, the plugin is one whose CI is permitted
+     * to skip specs tagged with these features — but is also required
+     * to make those specs FAIL (i.e. the plugin must actually disable
+     * what it declares). Surfaced in the plugin card so users see what
+     * a plugin removes before installing.
+     *
+     * May be undefined for plugins that don't disable any baseline
+     * feature, which is the common case.
+     */
+    disables?: string[]
 }