feat: add textbox content extraction in msword_backend

Signed-off-by: Andrew <tsai247365@gmail.com>

tests/test_backend_msword.py

@@ -16,6 +16,27 @@ from .verify_utils import verify_document, verify_export
 GENERATE = GEN_TEST_DATA
 
 
+def test_textbox_extraction():
+    in_path = Path("tests/data/docx/textbox.docx")
+    in_doc = InputDocument(
+        path_or_stream=in_path,
+        format=InputFormat.DOCX,
+        backend=MsWordDocumentBackend,
+    )
+    backend = MsWordDocumentBackend(
+        in_doc=in_doc,
+        path_or_stream=in_path,
+    )
+    doc = backend.convert()
+
+    # Verify if a particular textbox content is extracted
+    textbox_found = False
+    for item, _ in doc.iterate_items():
+        if item.text[:30] == """Suggested Reportable Symptoms:""":
+            textbox_found = True
+    assert textbox_found
+
+
 def test_heading_levels():
     in_path = Path("tests/data/docx/word_sample.docx")
     in_doc = InputDocument(