feat(gemini-cli): add multi-project support and enhance credential handling

Introduce support for multi-project Gemini CLI logins, including shared and virtual credential management. Enhance runtime, metadata handling, and token updates for better project granularity and consistency across virtual and shared credentials. Extend onboarding to allow activating all available projects.

internal/watcher/watcher.go

@@ -21,6 +21,7 @@ import (
 
 	"github.com/fsnotify/fsnotify"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
+	"github.com/router-for-me/CLIProxyAPI/v6/internal/runtime/geminicli"
 	"gopkg.in/yaml.v3"
 
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/util"
@@ -1026,11 +1027,119 @@ func (w *Watcher) SnapshotCoreAuths() []*coreauth.Auth {
 			CreatedAt: now,
 			UpdatedAt: now,
 		}
+		if provider == "gemini-cli" {
+			if virtuals := synthesizeGeminiVirtualAuths(a, metadata, now); len(virtuals) > 0 {
+				out = append(out, a)
+				out = append(out, virtuals...)
+				continue
+			}
+		}
 		out = append(out, a)
 	}
 	return out
 }
 
+func synthesizeGeminiVirtualAuths(primary *coreauth.Auth, metadata map[string]any, now time.Time) []*coreauth.Auth {
+	if primary == nil || metadata == nil {
+		return nil
+	}
+	projects := splitGeminiProjectIDs(metadata)
+	if len(projects) <= 1 {
+		return nil
+	}
+	email, _ := metadata["email"].(string)
+	shared := geminicli.NewSharedCredential(primary.ID, email, metadata, projects)
+	primary.Disabled = true
+	primary.Status = coreauth.StatusDisabled
+	primary.Runtime = shared
+	if primary.Attributes == nil {
+		primary.Attributes = make(map[string]string)
+	}
+	primary.Attributes["gemini_virtual_primary"] = "true"
+	primary.Attributes["virtual_children"] = strings.Join(projects, ",")
+	source := primary.Attributes["source"]
+	authPath := primary.Attributes["path"]
+	originalProvider := primary.Provider
+	if originalProvider == "" {
+		originalProvider = "gemini-cli"
+	}
+	label := primary.Label
+	if label == "" {
+		label = originalProvider
+	}
+	virtuals := make([]*coreauth.Auth, 0, len(projects))
+	for _, projectID := range projects {
+		attrs := map[string]string{
+			"runtime_only":           "true",
+			"gemini_virtual_parent":  primary.ID,
+			"gemini_virtual_project": projectID,
+		}
+		if source != "" {
+			attrs["source"] = source
+		}
+		if authPath != "" {
+			attrs["path"] = authPath
+		}
+		metadataCopy := map[string]any{
+			"email":             email,
+			"project_id":        projectID,
+			"virtual":           true,
+			"virtual_parent_id": primary.ID,
+			"type":              metadata["type"],
+		}
+		proxy := strings.TrimSpace(primary.ProxyURL)
+		if proxy != "" {
+			metadataCopy["proxy_url"] = proxy
+		}
+		virtual := &coreauth.Auth{
+			ID:         buildGeminiVirtualID(primary.ID, projectID),
+			Provider:   originalProvider,
+			Label:      fmt.Sprintf("%s [%s]", label, projectID),
+			Status:     coreauth.StatusActive,
+			Attributes: attrs,
+			Metadata:   metadataCopy,
+			ProxyURL:   primary.ProxyURL,
+			CreatedAt:  now,
+			UpdatedAt:  now,
+			Runtime:    geminicli.NewVirtualCredential(projectID, shared),
+		}
+		virtuals = append(virtuals, virtual)
+	}
+	return virtuals
+}
+
+func splitGeminiProjectIDs(metadata map[string]any) []string {
+	raw, _ := metadata["project_id"].(string)
+	trimmed := strings.TrimSpace(raw)
+	if trimmed == "" {
+		return nil
+	}
+	parts := strings.Split(trimmed, ",")
+	result := make([]string, 0, len(parts))
+	seen := make(map[string]struct{}, len(parts))
+	for _, part := range parts {
+		id := strings.TrimSpace(part)
+		if id == "" {
+			continue
+		}
+		if _, ok := seen[id]; ok {
+			continue
+		}
+		seen[id] = struct{}{}
+		result = append(result, id)
+	}
+	return result
+}
+
+func buildGeminiVirtualID(baseID, projectID string) string {
+	project := strings.TrimSpace(projectID)
+	if project == "" {
+		project = "project"
+	}
+	replacer := strings.NewReplacer("/", "_", "\\", "_", " ", "_")
+	return fmt.Sprintf("%s::%s", baseID, replacer.Replace(project))
+}
+
 // buildCombinedClientMap merges file-based clients with API key clients from the cache.
 // buildCombinedClientMap removed