Update README with data descriptions and alignment states; remove old screenshot

- Clarified sections on real and fabricated data in the README.
- Added detailed descriptions of alignment states with corresponding conditions and visual indicators.
- Removed outdated screenshot and added new images for each alignment state (Ready, Aligning, Fault).

README.md

@@ -1,6 +1,6 @@
 # Wafer Position Monitor (demo)
 
-PySide6 desktop demo: load NanoBerry edge CSVs from `MASTER_SD/`, fit a wafer circle, show **X / Y / theta** offset and **sigma** vs a calibration baseline. No live camera required.
+PySide6 desktop demo: load NanoBerry edge CSVs from `MASTER_SD/`, fit a wafer circle, show **X / Y / theta** offset and **sigma** vs a calibration baseline. No live camera integrated yet.
 
 **Stack:** Python 3.11+, PySide6, NumPy.
 
@@ -14,11 +14,11 @@ wafer-user          # or: python src/wafer_edge/App.py
 
 Click **Read Wafer** to load the demo CSVs. Tests: `python -m pytest tests/` (UI smoke needs a display).
 
-## Demo data
+## Data
 
-CSV files in `[MASTER_SD/](MASTER_SD/)`. Names: `{S|R}{1|2}{seq}P0.CSV` — local/remote board, SPI camera, 4-digit sequence (e.g. `S10540P0.CSV`).
+**Real data** — `[MASTER_SD/](MASTER_SD/)`: CSV files from actual NanoBerry camera captures. Names: `{S|R}{1|2}{seq}P0.CSV` — local/remote board, SPI camera, 4-digit sequence (e.g. `S10540P0.CSV`).
 
-Default cameras: `CsvSource.DEMO_CAMERA_PATHS`. Change that dict or use `parse_csv_filename()` for other captures.
+**Fabricated data** — `[DATA/0610/](DATA/)`: Generated test data used by `CsvSource.DEMO_CAMERA_PATHS` (the default demo source). Change that dict or use `parse_csv_filename()` for other captures.
 
 ## Calibration
 
@@ -36,4 +36,24 @@ First run creates `baseline.json` (gitignored). Key fields: `center_mm`, `radius
 
 **Pipeline:** `DEMO_CAMERA_PATHS` → `load_camera_records_from_csv()` → `snapshot_from_records()` → UI.
 
-![APP screenshot](screenshot.png)
+## Alignment states
+
+The monitor derives one of three states from the fitted circle on every read:
+
+| State        | Condition                            | Dot      |
+| ------------ | ------------------------------------ | -------- |
+| **Ready**    | offset ≤ 0.10 mm **and** σ ≤ 0.05 mm | 🟢 green |
+| **Aligning** | offset ≤ 0.50 mm **and** σ ≤ 0.20 mm | 🟡 amber |
+| **Fault**    | offset > 0.50 mm **or** σ > 0.20 mm  | 🔴 red   |
+
+### Ready — wafer within tolerance
+
+![Ready state](screenshots/state_ready.png)
+
+### Aligning — wafer correcting, noisy cameras
+
+![Aligning state](screenshots/state_aligning.png)
+
+### Fault — wafer out of range
+
+![Fault state](screenshots/state_fault.png)