fix: address round 2 Copilot feedback

- Pass table_name to op.drop_index in migration 019 downgrade for
  dialect portability
- Fix dedup comment accuracy (first occurrence wins, not highest version)
- Re-render registry cards on install failure to reset stuck
  "Installing..." button state

turnstone/console/server.py

@@ -3190,8 +3190,8 @@ async def admin_registry_search(request: Request) -> JSONResponse:
         except MCPRegistryError as exc:
             return JSONResponse({"error": f"Registry error: {exc}"}, status_code=502)
 
-    # Deduplicate: keep only isLatest entries, then by name (highest version)
-    # Skip servers with no install source (no remotes and no packages)
+    # Deduplicate: keep only isLatest entries, first occurrence per name wins.
+    # Skip servers with no install source (no remotes and no packages).
     seen: dict[str, RegistryServer] = {}
     for srv in result.servers:
         if srv.meta and not srv.meta.is_latest:

turnstone/console/static/admin.js

@@ -3826,6 +3826,8 @@ function _doRegistryInstall(
         errEl.style.display = "";
       } else {
         showToast("Install failed: " + e.message);
+        // Re-render to reset card button states
+        _renderRegistryResults();
       }
     })
     .finally(function () {

turnstone/core/storage/migrations/versions/019_mcp_registry.py

@@ -31,7 +31,7 @@ def upgrade() -> None:
 
 
 def downgrade() -> None:
-    op.drop_index("idx_mcp_servers_registry_name")
+    op.drop_index("idx_mcp_servers_registry_name", table_name="mcp_servers")
     op.drop_column("mcp_servers", "registry_meta")
     op.drop_column("mcp_servers", "registry_version")
     op.drop_column("mcp_servers", "registry_name")