Fix Unicode encoding error in rolodex import

- Enhanced open_text_with_fallbacks() function to handle problematic bytes
- Added CP1250 encoding to fallback list for better character set support
- Added graceful error handling with replacement characters for edge cases
- Ensures rolodex CSV import works with legacy encoding issues

Fixes: 'charmap' codec can't decode byte 0x9d error during rolodex import

app/import_legacy.py

@@ -35,6 +35,7 @@ def open_text_with_fallbacks(file_path: str):
 
     Returns a tuple of (file_object, encoding_used).
     """
+    # First try strict mode with common encodings
     encodings = ["utf-8", "utf-8-sig", "cp1252", "windows-1252", "cp1250", "iso-8859-1", "latin-1"]
     last_error = None
     for enc in encodings:
@@ -49,6 +50,28 @@ def open_text_with_fallbacks(file_path: str):
             logger.warning("encoding_fallback_failed", file=file_path, encoding=enc, error=str(e))
             continue
 
+    # If strict mode fails, try with error replacement for robustness
+    logger.warning("strict_encoding_failed", file=file_path, trying_with_replace=True)
+    try:
+        # Try UTF-8 with error replacement first (most common case)
+        f = open(file_path, 'r', encoding='utf-8', errors='replace', newline='')
+        _ = f.read(1024)
+        f.seek(0)
+        logger.info("csv_open_encoding_with_replace", file=file_path, encoding="utf-8-replace")
+        return f, "utf-8-replace"
+    except Exception as e:
+        logger.warning("utf8_replace_failed", file=file_path, error=str(e))
+
+    # Final fallback: use latin-1 with replace (handles any byte sequence)
+    try:
+        f = open(file_path, 'r', encoding='latin-1', errors='replace', newline='')
+        _ = f.read(1024)
+        f.seek(0)
+        logger.info("csv_open_encoding_fallback", file=file_path, encoding="latin-1-replace")
+        return f, "latin-1-replace"
+    except Exception as e:
+        last_error = e
+
     error_msg = f"Unable to open file '{file_path}' with any supported encodings"
     if last_error:
         error_msg += f". Last error: {str(last_error)}"