update to garage sync

USECASES.md

@@ -104,10 +104,18 @@ for stateless static sites.
 
 ## 9. Upload media files
 
-**Trigger:** `aws s3 cp` or `aws s3 sync` to `s3://example.com/`.
+**Trigger:** `aws s3 cp` or `aws s3 sync` to `s3://example.com/`, or `./media.sh push` from a site repo.
 
 **Expected outcome:**
 - File uploaded via S3 API (`s3.hantim.net`)
 - Replicated to both Garage nodes (hantim + argento)
 - Accessible at `https://www.example.com/media/<path>`
-- Local development: `static/media/` (gitignored) serves at `/media/`
+
+## 10. Local development with media files
+
+**Trigger:** `./media.sh pull` from a site repo.
+
+**Expected outcome:**
+- Media files downloaded from Garage to `static/media/` (gitignored)
+- Files served locally at `/media/` by the app container's nginx
+- To upload local changes back to Garage: `./media.sh push`