docs(qr_codes): steps to run workflow, and CLI help

Author: thekaveman

qr_codes/README.md

@@ -0,0 +1,42 @@
+# Generate QR codes
+
+> Generate a QR code as an PNG file
+
+## Run in GitHub
+
+1. Go to the `Actions` tab at the top of this repository
+1. In the left bar, select the `Generate QR code` workflow
+1. Click the gray `Run workflow` button on the right side, providing inputs as-needed:
+
+   - `branch` should be left as `main`
+   - `data` is required, this is the URL the QR code should point to
+   - `color`, `background`, and `size` are optional
+
+1. Click the green `Run workflow` button
+1. Refresh the page to see the in-progress workflow run
+1. When the workflow has completed (look for the green check mark), click the run
+1. In the bottom pane under `Artifacts`, find a link to download the QR code image (downloads a ZIP file with the image inside)
+
+## Run locally
+
+1. Open this repository's devcontainer in VS Code
+2. Change into the `qr_codes` directory
+3. Run the helper script
+
+```bash
+$ python main.py -h
+usage: main.py [-h] [--color COLOR] [--background BACKGROUND] [--size SIZE] data output
+
+Generate a QR code as an PNG file
+
+positional arguments:
+  data                  The data to encode as a QR code
+  output                Path to an PNG file where the QR code is written
+
+options:
+  -h, --help            show this help message and exit
+  --color COLOR         The color of the QR code in hex format, by default black
+  --background BACKGROUND
+                        The background color of the QR code in hex format, by default transparent
+  --size SIZE           The QR code size from 1-10, by default 4
+```