gen-cards: regenerate Use-it block

README.md

@@ -21,6 +21,46 @@ Diffusion 2.1 UNet + a half-size VAE decoder, run in **one forward pass** — no
 no prompt, no noise — so it is fast and small enough to run fully on-device, including iPhone.
 
 <!-- gen-cards:use-it begin id=adcsr-x4 (managed by scripts/gen-cards — edit cards.json / QuickStart.swift, not this block) -->
+## Use it
+
+▶️ **Run it (source)** — the [UpscaleDemo runner](https://github.com/john-rocky/coreai-kit/tree/main/Examples/UpscaleDemo)
+(pick a photo, upscale it ×4 on-device):
+
+```bash
+git clone https://github.com/john-rocky/coreai-kit
+open coreai-kit/Examples/UpscaleDemo/UpscaleDemo.xcodeproj
+# → Run, pick a photo — the app loads AdcSR ×4 (the catalog's superResolution entry) automatically
+
+# agents / headless (macOS):
+cd coreai-kit/Examples/UpscaleDemo
+swift run upscale-cli --model adcsr-x4 --image sample_small.png --output big.png
+```
+
+💻 **Build with it** — complete; the glue is kit API, copy-paste runs:
+
+```swift
+import CoreAIKitVision
+
+let resolver = try await SuperResolver(catalog: "adcsr-x4")
+let image = try ImageFile.load(imageURL)  // any image file → CGImage + EXIF orientation
+let upscaled = try await resolver.upscale(image.cgImage)
+// upscaled: CGImage — 4× the input's pixels
+```
+
+The take-home is [`Examples/UpscaleDemo/Sources/QuickStart.swift`](https://github.com/john-rocky/coreai-kit/blob/main/Examples/UpscaleDemo/Sources/QuickStart.swift)
+— this exact code as one typed function, no UI; the CLI is an argument shell over it, and
+the GUI runs the same resolver on the photo you pick.
+Big photos? Inputs are tiled and feather-blended internally; `maxInputSide` (default 512)
+caps the input first so a full-res phone photo can't produce a gigapixel result.
+
+**Integration checklist**
+
+- SPM: `https://github.com/john-rocky/coreai-kit` → product **CoreAIKitVision**
+- Info.plist: none needed
+- Entitlements: none needed
+- First run downloads the model — 1.7 GB (Mac) / 1.7 GB (iPhone) — then it loads from the
+  local cache (Application Support; progress via the `downloadProgress` callback)
+- Measure in Release — Debug is ~3× slower on per-token host work
 <!-- gen-cards:use-it end -->
 
 ## What it is