docs: Describe examples (#2262)

* Update .py examples with clearer guidance,
update out of date imports and calls

Signed-off-by: Mingxuan Zhao <43148277+mingxzhao@users.noreply.github.com>

* Fix minimal.py string error, fix ruff format error

Signed-off-by: Mingxuan Zhao <43148277+mingxzhao@users.noreply.github.com>

* fix more CI issues

Signed-off-by: Mingxuan Zhao <43148277+mingxzhao@users.noreply.github.com>

---------

Signed-off-by: Mingxuan Zhao <43148277+mingxzhao@users.noreply.github.com>

docs/examples/minimal.py

@@ -1,9 +1,32 @@
+# %% [markdown]
+# Simple conversion: one document to Markdown
+# ==========================================
+#
+# What this example does
+# - Converts a single source (URL or local file path) to a unified Docling
+#   document and prints Markdown to stdout.
+#
+# Requirements
+# - Python 3.9+
+# - Install Docling: `pip install docling`
+#
+# How to run
+# - Use the default sample URL: `python docs/examples/minimal.py`
+# - To use your own file or URL, edit the `source` variable below.
+#
+# Notes
+# - The converter auto-detects supported formats (PDF, DOCX, HTML, PPTX, images, etc.).
+# - For batch processing or saving outputs to files, see `docs/examples/batch_convert.py`.
+
 from docling.document_converter import DocumentConverter
 
-source = "https://arxiv.org/pdf/2408.09869"  # document per local path or URL
+# Change this to a local path or another URL if desired.
+# Note: using the default URL requires network access; if offline, provide a
+# local file path (e.g., Path("/path/to/file.pdf")).
+source = "https://arxiv.org/pdf/2408.09869"
 
 converter = DocumentConverter()
-doc = converter.convert(source).document
+result = converter.convert(source)
 
-print(doc.export_to_markdown())
-# output: ## Docling Technical Report [...]"
+# Print Markdown to stdout.
+print(result.document.export_to_markdown())