execute: add jq, expect, bc support

jq: filter as positional arg, file args appended, pipeline-safe.
expect: pipes script via printf '%s' $'...' | expect -.
bc: pipes via printf '%s' $'...' | bc -ql (quiet + math library).
All three use ANSI-C quoting consistently.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pkg/tools/execute/pipe.go

@@ -59,6 +59,10 @@ func BuildPipeline(steps []PipeStep) (string, bool, error) {
 			parts = append(parts, fmt.Sprintf("( gawk -e $'%s' )", ansiCEscape(code)))
 		case "sed":
 			parts = append(parts, fmt.Sprintf("( sed -e $'%s' )", ansiCEscape(code)))
+		case "jq":
+			parts = append(parts, fmt.Sprintf("( jq $'%s' )", ansiCEscape(code)))
+		case "bc":
+			parts = append(parts, fmt.Sprintf("( bc -ql <<< $'%s' )", ansiCEscape(code)))
 		default:
 			parts = append(parts, fmt.Sprintf("(\n%s\n)", code))
 		}

pkg/tools/execute/server.go

@@ -82,7 +82,7 @@ Examples:
 
 Usage:
 - Scripts located in: ` + ToolsPath() + `
-- Supported languages: bash, python3, perl, awk, sed, ed (detected from shebang)
+- Supported languages: bash, python3, perl, awk, sed, ed, jq, expect, bc (detected from shebang)
 - Use for named scripts, not inline shell commands
 - Default timeout: 30 seconds
 
@@ -256,10 +256,15 @@ func (e *Server) Execute(ctx context.Context, code, language string, timeout int
 	case "sed":
 		interpreter = []string{"bash", "-c", fmt.Sprintf("sed -e $'%s'", ansiCEscape(code))}
 	case "ed":
-		// ed reads commands from stdin; no filename = edit new buffer.
 		interpreter = []string{"bash", "-c", fmt.Sprintf("printf '%%s' $'%s' | ed -s", ansiCEscape(code))}
+	case "jq":
+		interpreter = []string{"bash", "-c", fmt.Sprintf("jq $'%s'", ansiCEscape(code))}
+	case "expect":
+		interpreter = []string{"bash", "-c", fmt.Sprintf("printf '%%s' $'%s' | expect -", ansiCEscape(code))}
+	case "bc":
+		interpreter = []string{"bash", "-c", fmt.Sprintf("printf '%%s' $'%s' | bc -ql", ansiCEscape(code))}
 	default:
-		return "", fmt.Errorf("unsupported language: %s (supported: bash, python3, perl, awk, sed, ed)", language)
+		return "", fmt.Errorf("unsupported language: %s (supported: bash, python3, perl, awk, sed, ed, jq, expect, bc)", language)
 	}
 	wrapped := sandbox.WrapCommand(cfg, interpreter, workDir)
 	cmd = exec.CommandContext(ctx, wrapped[0], wrapped[1:]...)

pkg/tools/execute/tool.go

@@ -50,6 +50,12 @@ func detectLanguage(code string) string {
 		return "sed"
 	case "ed":
 		return "ed"
+	case "jq":
+		return "jq"
+	case "expect":
+		return "expect"
+	case "bc":
+		return "bc"
 	}
 	return "bash"
 }
@@ -90,6 +96,19 @@ func injectArgs(language, name string, args []string, code string) string {
 			file = " '" + strings.ReplaceAll(args[0], "'", "'\\''") + "'"
 		}
 		return fmt.Sprintf("printf '%%s' $'%s' | ed -s%s", ansiCEscape(code), file)
+	case "jq":
+		// jq args are JSON input files; filter is the program.
+		fileArgs := make([]string, len(args))
+		for i, a := range args {
+			fileArgs[i] = "'" + strings.ReplaceAll(a, "'", "'\\''") + "'"
+		}
+		return fmt.Sprintf("jq $'%s' %s", ansiCEscape(code), strings.Join(fileArgs, " "))
+	case "expect":
+		// expect reads script from stdin via expect -.
+		return fmt.Sprintf("printf '%%s' $'%s' | expect -", ansiCEscape(code))
+	case "bc":
+		// bc reads from stdin; -ql for quiet mode + math library.
+		return fmt.Sprintf("printf '%%s' $'%s' | bc -ql", ansiCEscape(code))
 	default: // bash
 		escaped := make([]string, len(args))
 		for i, a := range args {