feat: add project export and import functionality

- Implemented `pcli project export` command to export project hierarchy as JSON.
- Added `pcli project import` command to import project data from JSON.
- Created user client to fetch user details for comment attribution.
- Introduced new data structures for export and import processes.
- Ensured name-based references in exports and handled conflicts during imports.
- Added versioning and progress reporting for import operations.
- Updated documentation and specifications for new features.

cmd/resolve.go

@@ -0,0 +1,43 @@
+package cmd
+
+import (
+	"fmt"
+	"strings"
+)
+
+// resolveProject takes a project ID or name and returns the project ID.
+// If the input matches a project ID exactly, it's returned directly.
+// If it matches project name(s), it returns the ID if exactly one matches.
+func resolveProject(idOrName string) (string, error) {
+	// First try as an ID
+	project, err := getClient().GetProject(getContext(), idOrName)
+	if err == nil {
+		return project.ID, nil
+	}
+
+	// Fall back to name lookup
+	projects, err := getClient().ListProjects(getContext())
+	if err != nil {
+		return "", fmt.Errorf("failed to list projects: %w", err)
+	}
+
+	var matches []struct{ id, name string }
+	for _, p := range projects {
+		if strings.EqualFold(p.Name, idOrName) {
+			matches = append(matches, struct{ id, name string }{p.ID, p.Name})
+		}
+	}
+
+	switch len(matches) {
+	case 0:
+		return "", fmt.Errorf("project %q not found", idOrName)
+	case 1:
+		return matches[0].id, nil
+	default:
+		var names []string
+		for _, m := range matches {
+			names = append(names, fmt.Sprintf("%s (%s)", m.name, m.id))
+		}
+		return "", fmt.Errorf("ambiguous project name %q matches multiple projects: %s", idOrName, strings.Join(names, ", "))
+	}
+}