feat(inbounds): support Unix domain socket path in Listen field (#4429)

UDS listen already worked for proxying (the listen string is passed to xray verbatim and port 0 is accepted), and the Go sub/link layer already ignores the bind listen. The only gap was the frontend resolveAddr, which would put a socket-path listen into share/sub links (e.g. vless://uuid@/run/xray/x.sock:0). resolveAddr now treats a path-style listen (starting with / or @) as having no client-reachable address and falls back to hostOverride/hostname. Adds a test and a Listen-field help hint across all locales.

frontend/src/test/inbound-link.test.ts

@@ -196,6 +196,19 @@ describe('resolveAddr precedence', () => {
     )).toBe('fallback.test');
   });
 
+  it('skips a unix socket path listen and falls through to fallbackHostname', () => {
+    expect(resolveAddr(
+      { ...baseInbound, listen: '/run/xray/in.sock' } as never,
+      '',
+      'fallback.test',
+    )).toBe('fallback.test');
+    expect(resolveAddr(
+      { ...baseInbound, listen: '@xray-abstract' } as never,
+      '',
+      'fallback.test',
+    )).toBe('fallback.test');
+  });
+
   it('falls through to fallbackHostname when listen is empty', () => {
     expect(resolveAddr(
       baseInbound as never,