agent: Improve the UX around interacting with MCP servers (#32622)

Still a work in progress! Todos before merging:

- [x] Allow to delete (not just turn off) an MCP server from the panel's
settings view
- [x] Also uninstall the extension upon deleting the server (check if
the extension just provides MCPs)
- [x] Resolve repository URL again
- [x] Add a button to open the configuration modal from the panel's
settings view
- [x] Improve modal UX to install and configure a non-extension MCP

Release Notes:

- N/A

---------

Co-authored-by: Bennet Bo Fenner <bennetbo@gmx.de>
Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>

crates/extensions_ui/src/extensions_ui.rs

@@ -583,7 +583,7 @@ impl ExtensionsPage {
                                         let extension_id = extension.id.clone();
                                         move |_, _, cx| {
                                             ExtensionStore::global(cx).update(cx, |store, cx| {
-                                                store.uninstall_extension(extension_id.clone(), cx)
+                                                store.uninstall_extension(extension_id.clone(), cx).detach_and_log_err(cx);
                                             });
                                         }
                                     }),
@@ -983,7 +983,9 @@ impl ExtensionsPage {
                     move |_, _, cx| {
                         telemetry::event!("Extension Uninstalled", extension_id);
                         ExtensionStore::global(cx).update(cx, |store, cx| {
-                            store.uninstall_extension(extension_id.clone(), cx)
+                            store
+                                .uninstall_extension(extension_id.clone(), cx)
+                                .detach_and_log_err(cx);
                         });
                     }
                 }),