Add import/export and backup system (Milestone 8)

- Obsidian vault importer with wikilink → edge conversion
- Markdown folder importer with frontmatter parsing
- Markdown exporter with wikilinks and frontmatter
- JSON-LD linked data exporter
- Database backup/restore functionality
- CLI: import, backup, restore-backup, list-backups
- MCP tools: memory_import, memory_backup, memory_export_markdown, memory_export_jsonld

src/cli/index.ts

@@ -20,6 +20,8 @@ import { indexCommand } from './commands/index-cmd';
 import { journalCommand, journalAliasCommand, quickCaptureCommand } from './commands/journal';
 import { ingestCommand, clipCommand } from './commands/ingest';
 import { exportCommand, vizCommand } from './commands/export';
+import { importCommand } from './commands/import';
+import { backupCommand, restoreDbCommand, listBackupsCommand } from './commands/backup-cmd';
 import { closeDb } from '../core/db';
 
 const program = new Command();
@@ -56,6 +58,10 @@ program.addCommand(ingestCommand);
 program.addCommand(clipCommand);
 program.addCommand(exportCommand);
 program.addCommand(vizCommand);
+program.addCommand(importCommand);
+program.addCommand(backupCommand);
+program.addCommand(restoreDbCommand);
+program.addCommand(listBackupsCommand);
 
 program.hook('postAction', () => {
   closeDb();