feat(api-docs): enhance in-panel API documentation (#4312)

* feat(api-docs): enhance API documentation with missing endpoints, search, collapse, and route sync test

- Add 29 undocumented routes across 4 new sections (Settings, Xray Settings,
  Subscription Server, WebSocket) plus 4 missing Server API endpoints
- Fix inaccuracies: history metric keys, node metric keys, VLESS enc description
- Add response schemas to 15+ key endpoints
- Add search bar and expand/collapse all controls to the docs page
- Add collapsible endpoint sections with endpoint count
- Add Go test (TestAPIRoutesDocumented) to verify all Go routes are documented

* feat(api-docs): add JSON syntax highlighting and top-right copy button to code blocks

* fix(api-docs): use distinct colors for JSON syntax highlighting (green strings, amber numbers)

* feat(api-docs): add request body examples, error responses, WebSocket message types, and subscription response headers

* fix(api-docs): use ClipboardManager.copyText instead of copy to fix API token copy button

web/controller/api_docs_test.go

@@ -0,0 +1,160 @@
+package controller
+
+import (
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+	"testing"
+)
+
+type routeDef struct {
+	Method string
+	Path   string
+}
+
+// routePattern matches route registrations like g.GET("/path", handler) or api.GET("/path", handler)
+var routePattern = regexp.MustCompile(`\b(g|api)\.(GET|POST|PUT|DELETE|PATCH|HEAD|OPTIONS)\("([^"]+)"`)
+
+// docRoutePattern matches { method: 'X', path: 'Y' ... } entries in endpoints.js.
+var docRoutePattern = regexp.MustCompile(`method:\s*'([A-Z]+)'\s*,\s*path:\s*'([^']+)'`)
+
+// buildDocSet parses frontend/src/pages/api-docs/endpoints.js and returns the
+// set of documented "METHOD PATH" keys. WS pseudo-routes and subscription
+// placeholders (paths starting with /{...}) are skipped because they aren't
+// registered on the main Gin engine.
+func buildDocSet(t *testing.T) map[string]bool {
+	t.Helper()
+	controllerDir, err := filepath.Abs(".")
+	if err != nil {
+		t.Fatalf("failed to get current dir: %v", err)
+	}
+	endpointsPath := filepath.Join(controllerDir, "..", "..", "frontend", "src", "pages", "api-docs", "endpoints.js")
+	data, err := os.ReadFile(endpointsPath)
+	if err != nil {
+		t.Fatalf("failed to read endpoints.js at %s: %v", endpointsPath, err)
+	}
+	docSet := make(map[string]bool)
+	for _, m := range docRoutePattern.FindAllStringSubmatch(string(data), -1) {
+		method, path := m[1], m[2]
+		if method == "WS" {
+			continue
+		}
+		if !strings.HasPrefix(path, "/") || strings.HasPrefix(path, "/{") {
+			continue
+		}
+		docSet[method+" "+path] = true
+	}
+	if len(docSet) == 0 {
+		t.Fatalf("no documented routes parsed from %s — regex or file format may have changed", endpointsPath)
+	}
+	return docSet
+}
+
+func TestAPIRoutesDocumented(t *testing.T) {
+	docSet := buildDocSet(t)
+
+	controllerDir, err := filepath.Abs(".")
+	if err != nil {
+		t.Fatalf("failed to get current dir: %v", err)
+	}
+
+	var allRoutes []routeDef
+
+	entries, err := os.ReadDir(controllerDir)
+	if err != nil {
+		t.Fatalf("failed to read controller dir: %v", err)
+	}
+
+	for _, entry := range entries {
+		if entry.IsDir() || !strings.HasSuffix(entry.Name(), ".go") || strings.HasSuffix(entry.Name(), "_test.go") {
+			continue
+		}
+		data, err := os.ReadFile(filepath.Join(controllerDir, entry.Name()))
+		if err != nil {
+			t.Fatalf("failed to read %s: %v", entry.Name(), err)
+		}
+		src := string(data)
+
+		// Determine the base path for this file based on its initRouter patterns
+		basePath := ""
+		switch entry.Name() {
+		case "index.go":
+			basePath = ""
+		case "xui.go":
+			basePath = "/panel"
+		case "api.go":
+			basePath = "/panel/api"
+		case "inbound.go":
+			basePath = "/panel/api/inbounds"
+		case "server.go":
+			basePath = "/panel/api/server"
+		case "node.go":
+			basePath = "/panel/api/nodes"
+		case "setting.go":
+			basePath = "/panel/setting"
+		case "xray_setting.go":
+			basePath = "/panel/xray"
+		case "custom_geo.go":
+			basePath = "/panel/api/custom-geo"
+		case "websocket.go":
+			basePath = ""
+		}
+
+		// Find all route registrations
+		matches := routePattern.FindAllStringSubmatch(src, -1)
+		for _, m := range matches {
+			method := m[2]
+			path := strings.TrimSpace(m[3])
+			if basePath == "" {
+				allRoutes = append(allRoutes, routeDef{Method: method, Path: path})
+			} else {
+				fullPath := basePath + path
+				allRoutes = append(allRoutes, routeDef{Method: method, Path: fullPath})
+			}
+		}
+	}
+
+	// The WebSocket route /ws is registered in web/web.go (not a controller file)
+	allRoutes = append(allRoutes, routeDef{Method: "GET", Path: "/ws"})
+
+	missingFromDocs := 0
+	foundInDoc := 0
+	sourceSet := make(map[string]bool)
+
+	for _, r := range allRoutes {
+		key := r.Method + " " + r.Path
+		// Skip SPA page routes (these are UI pages, not API endpoints)
+		spaPages := map[string]bool{
+			"/": true, "/panel/": true, "/panel/inbounds": true,
+			"/panel/nodes": true, "/panel/settings": true,
+			"/panel/xray": true, "/panel/api-docs": true,
+		}
+		if spaPages[r.Path] {
+			continue
+		}
+		// Skip /panel/csrf-token (documented under auth as /csrf-token)
+		if r.Path == "/panel/csrf-token" {
+			continue
+		}
+		// Skip Chrome DevTools route
+		if strings.Contains(r.Path, ".well-known") {
+			continue
+		}
+
+		sourceSet[key] = true
+		if docSet[key] {
+			foundInDoc++
+		} else {
+			missingFromDocs++
+			t.Errorf("Route not documented in endpoints.js: %s %s", r.Method, r.Path)
+		}
+	}
+
+	t.Logf("Routes found in source: %d, documented: %d, matching: %d, missing: %d",
+		len(sourceSet), len(docSet), foundInDoc, missingFromDocs)
+
+	if missingFromDocs > 0 {
+		t.Errorf("Found %d undocumented route(s). Update endpoints.js to match.", missingFromDocs)
+	}
+}