clicking a plugin works again, and offscale gets its icon

Two regressions and one long-standing hole, all found by actually opening the page.

── Clicking a row did nothing. That one is mine ──

Rows link to `?selected=<app>`, and they still pointed at `/plugins`. My redirect
was `<Navigate to="/marketplace" replace />`, which DROPS the query string — so a
click went to `/plugins?selected=music`, redirected to a bare `/marketplace`, and
the detail pane sat on "Select a plugin." Both halves worked; the redirect threw
away what the link had just set.

Rows now point at `/marketplace` directly. The redirect also preserves `search`,
because old bookmarks carry the same param and losing it is exactly what made this
wrong the first time.

── Offscale's icon 404'd since it shipped one ──

Assets were published to `public/plugins/<app>/` at INSTALL and nowhere else.
Offscale was installed before it had an `assets/icon.png`, so the directory never
existed and the tile drew a 404 permanently — nothing short of uninstalling and
reinstalling would have fixed it. "Reinstall the plugin to see its new icon" is
the same bad answer as "restart the server to see it", which the route right next
to this already refuses to accept.

Publishing now happens on every mount. It is a copy of files that still exist in
the plugin's own source, so re-running it is free and cannot lose anything — the
property that already makes unpublish the one thing uninstall may delete. A
failure is logged, never thrown: an icon is not worth refusing to mount over.

Published offscale's by hand too, so the fix is visible without waiting for a
restart. Verified 200 through the running server for both plugins.

── The third report was not a bug ──

"No connection to the marketplace" is the catalogue working correctly: all three
plugins are already on disk here, and `router.ts` drops catalogue entries whose
plugin is installed, because offering to install something installed is worse than
showing nothing. With nothing left to offer, a working store and a broken one look
identical on that screen. Nothing in the logs, which is what a reachable store
looks like — the client only speaks when it cannot reach one.

tsgo clean, frontend builds, 873 pass / 7 fail unchanged.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/workspaces/officerdev/src/apps/Plugins/PluginsList.tsx

@@ -34,7 +34,7 @@ export const PluginsList = () => {
       {plugins.map((plugin) => (
         <Link
           key={plugin.appName}
-          to={`/plugins?selected=${encodeURIComponent(plugin.appName)}`}
+          to={`/marketplace?selected=${encodeURIComponent(plugin.appName)}`}
           className={`flex items-center gap-3 px-3 py-2.5 border-b border-duck-dark/5 transition-colors ${
             selected === plugin.appName ? 'bg-duck-teal/10' : 'hover:bg-duck-dark/5'
           }`}
@@ -73,7 +73,7 @@ export const PluginsList = () => {
       {available.map((plugin) => (
         <Link
           key={`available-${plugin.appName}`}
-          to={`/plugins?selected=${encodeURIComponent(plugin.appName)}`}
+          to={`/marketplace?selected=${encodeURIComponent(plugin.appName)}`}
           className={`flex items-center gap-3 border-b border-duck-dark/5 px-3 py-2.5 transition-colors ${
             selected === plugin.appName ? 'bg-duck-teal/10' : 'hover:bg-duck-dark/5'
           }`}