fix: harden home clash-mode card against /configs read failures

Recover from controller read/switch failures on the mode card instead of
showing a bare "communication error":

- fall back to the tolerant get_clash_mode command (then runtime config)
  when the live /configs mode is unavailable,
- optimistically reflect the clicked mode and write it through to the
  getClashConfig cache so a failed refetch can't flash back the old value,
- surface patch failures via showNotice on both the home card and the
  proxies page (patchClashMode can now reject), and
- revalidate getClashMode/getRuntimeConfig on refresh-clash-config so a
  once-empty fallback can recover.

src/services/cmds.ts

@@ -85,6 +85,12 @@ export async function getClashInfo() {
   return invoke<IClashInfo | null>('get_clash_info')
 }
 
+// Fault-tolerant current proxy mode read (does not depend on mihomo /configs
+// strict BaseConfig deserialization); used as a fallback for the home mode card.
+export async function getClashMode() {
+  return invoke<string | null>('get_clash_mode')
+}
+
 // Get runtime config which controlled by verge
 export async function getRuntimeConfig() {
   return invoke<IConfigData | null>('get_runtime_config')