fix: token persistence, context windows, CSS tables/bullets/hr, image attachments

- Fix token count reset on app restart: persist realTokens in conversation.json
- Fix token/context window values: Studio 150K (summarize at 120K), Terminal 100K
- Fix table rendering in terminal tab: correct thead/tbody display model
- Fix copy button always top-right in Studio code blocks
- Add markdown horizontal rule (---) support in Studio and Terminal
- Fix bullet list double dot: remove CSS ::before duplicate bullet point
- Add image attachments support (VLM description, file mentions @file.ext)
- Add sudo detection with cache (sync.Once)
- Fix message content serialization (TextContent wrapper)
- Guide AI to use read_file instead of cat in studio prompt

💘 Generated with Crush

Assisted-by: GLM-5.1 via Crush <crush@charm.land>

internal/api/handlers_info.go

@@ -12,6 +12,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/muyue/muyue/internal/agent"
 	"github.com/muyue/muyue/internal/lsp"
 	"github.com/muyue/muyue/internal/mcp"
 	"github.com/muyue/muyue/internal/scanner"
@@ -24,7 +25,7 @@ func (s *Server) handleInfo(w http.ResponseWriter, r *http.Request) {
 		"name":    version.Name,
 		"version": version.Version,
 		"author":  version.Author,
-		"sudo":    os.Geteuid() == 0,
+		"sudo":    !agent.NeedsSudoPassword(),
 	})
 }