fix(import): percent-decode share-link names preserving '+'; reject ambiguous bare IPv6

app/src/main/java/chat/vojo/proxy/core/ConfigImport.kt

@@ -55,6 +55,10 @@ private fun splitHostPort(hostPort: String): Pair<String, Int>? {
         val port = hp.substringAfterLast(':').toIntOrNull() ?: return null
         host to port
     } else {
+        // A bare (unbracketed) IPv6 literal has multiple colons and can't carry a port
+        // unambiguously — RFC 3986/5952 require brackets for IPv6+port. Reject rather than
+        // mis-split "fe80::1:8388" into a wrong host/port.
+        if (hp.count { it == ':' } > 1) return null
         val host = hp.substringBeforeLast(':')
         val port = hp.substringAfterLast(':').toIntOrNull() ?: return null
         host to port
@@ -62,7 +66,12 @@ private fun splitHostPort(hostPort: String): Pair<String, Int>? {
 }
 
 private fun parseSs(s: String): ProxyConfig? {
-    val name = s.substringAfter('#', "").let { runCatching { URLDecoder.decode(it, "UTF-8") }.getOrDefault(it) }
+    // Percent-decode the #fragment name. URLDecoder does form-decoding, so it would turn a
+    // literal '+' into a space (mangling names like "C++ box"); escape '+' first so only real
+    // %XX escapes are decoded — matching java.net.URI.getFragment() used by parseUri.
+    val name = s.substringAfter('#', "").let {
+        runCatching { URLDecoder.decode(it.replace("+", "%2B"), "UTF-8") }.getOrDefault(it)
+    }
     // SIP002 transport plugins (v2ray-plugin, obfs, …) aren't supported — a
     // config that needs one won't tunnel, so reject it rather than import a
     // silently-broken server.
@@ -114,7 +123,9 @@ private fun parseUri(s: String, type: ProxyType, defaultPort: Int): ProxyConfig?
     val port = if (uri.port > 0) uri.port else defaultPort
     val user = uri.userInfo?.substringBefore(':').orEmpty()
     val pass = uri.userInfo?.substringAfter(':', "").orEmpty()
-    val name = uri.fragment?.let { runCatching { URLDecoder.decode(it, "UTF-8") }.getOrDefault(it) }.orEmpty()
+    // URI.getFragment() is already percent-decoded; decoding again would turn '+'
+    // into a space and mangle names like "C++ box".
+    val name = uri.fragment.orEmpty()
     return ProxyConfig(
         name = name.ifBlank { host },
         type = type,