Release 4.0.0+1: rebrand Navis → EvilFox; centralized Remnawave auto-provisioning (panel credentials baked into binary); remove Remnawave API UI; Windows 4.0.0.1.

Keep dist/navis-release/ path and ship Navis.exe as a same-hash alias of EvilFox.exe so 3.x clients can still update from the Windows branch feed.

internal/remnawave/embedded.go

@@ -0,0 +1,51 @@
+package remnawave
+
+// Centralized (NordVPN-style) provisioning: the panel address and API token
+// are baked into the binary at build time, so every user gets configs
+// automatically and cannot change the panel.
+//
+// build.bat copies configs/remnawave-api.json into embeddedcfg/ before
+// `go build`; the copy is gitignored so credentials never land in the repo.
+// Without the embedded file the app falls back to the external
+// configs/remnawave-api.json (developer mode).
+
+import (
+	"crypto/rand"
+	"embed"
+	"encoding/hex"
+	"fmt"
+	"os"
+	"time"
+)
+
+//go:embed embeddedcfg
+var embeddedCfgFS embed.FS
+
+// EmbeddedAdminConfig returns the admin config baked into the binary,
+// or nil when this build has no embedded credentials.
+func EmbeddedAdminConfig() *AdminConfig {
+	data, err := embeddedCfgFS.ReadFile("embeddedcfg/remnawave-api.json")
+	if err != nil {
+		return nil
+	}
+	cfg, err := parseAdminConfig(data)
+	if err != nil {
+		return nil
+	}
+	return cfg
+}
+
+// GenerateUsername makes a unique panel username for silent auto-provisioning
+// (users never type anything): "fox_" + 10 hex chars, e.g. fox_3fa9c02b71.
+func GenerateUsername() string {
+	var b [5]byte
+	if _, err := rand.Read(b[:]); err != nil {
+		// Keep within Remnawave's 6–34 char username limit.
+		s := fmt.Sprintf("fox_%x%x", os.Getpid()&0xffff, time.Now().UnixNano()&0xffffffff)
+		if len(s) > 34 {
+			s = s[:34]
+		}
+		return s
+	}
+	return "fox_" + hex.EncodeToString(b[:])
+}