chore: import upstream snapshot with attribution

apps/sim/lib/file-parsers/md-parser.ts

@@ -0,0 +1,43 @@
+import { readFile } from 'fs/promises'
+import { createLogger } from '@sim/logger'
+import type { FileParseResult, FileParser } from '@/lib/file-parsers/types'
+import { sanitizeTextForUTF8 } from '@/lib/file-parsers/utils'
+
+const logger = createLogger('MdParser')
+
+export class MdParser implements FileParser {
+  async parseFile(filePath: string): Promise<FileParseResult> {
+    try {
+      if (!filePath) {
+        throw new Error('No file path provided')
+      }
+
+      const buffer = await readFile(filePath)
+
+      return this.parseBuffer(buffer)
+    } catch (error) {
+      logger.error('MD file error:', error)
+      throw new Error(`Failed to parse MD file: ${(error as Error).message}`)
+    }
+  }
+
+  async parseBuffer(buffer: Buffer): Promise<FileParseResult> {
+    try {
+      logger.info('Parsing buffer, size:', buffer.length)
+
+      const result = buffer.toString('utf-8')
+      const content = sanitizeTextForUTF8(result)
+
+      return {
+        content,
+        metadata: {
+          characterCount: content.length,
+          tokenCount: Math.floor(content.length / 4),
+        },
+      }
+    } catch (error) {
+      logger.error('MD buffer parsing error:', error)
+      throw new Error(`Failed to parse MD buffer: ${(error as Error).message}`)
+    }
+  }
+}