refactor(wsen-pads): Rewrite climate station with steami_screen widgets.

Major rewrite of the station_env example:

1. Use steami_screen (Screen, SSD1327Display, gauge, title, value,
   subtitle) instead of 100+ lines of pixel-by-pixel manual drawing
   (draw_hline, draw_vline, draw_rect, draw_fill_rect, draw_circle).
   The native framebuf primitives behind steami_screen are implemented
   in C and are orders of magnitude faster than Python pixel loops.

2. Remove fake calibration that forced readings toward arbitrary "ideal"
   values (20C, 50%RH, 1013hPa). A sensor reading 23C at startup was
   being shifted to 20C, making every subsequent reading wrong by -3C.
   The example now shows raw sensor values. For real calibration, use
   steami_config (see calibrate_temperature.py).

3. Translate all UI text and comments from French to English to match
   the project convention.

4. Add try/except/finally with power_off() for both sensors so Ctrl+C
   does not leave WSEN-PADS and HTS221 running.

5. Use named comfort thresholds (TEMP_MIN/MAX, HUM_MIN/MAX, PRES_MIN/MAX)
   instead of inline magic numbers.

Author: nedseb

lib/wsen-pads/examples/station_env.py

@@ -1,173 +1,93 @@
 """Climate station example using WSEN-PADS, HTS221 and SSD1327 OLED.
 
 Reads temperature and pressure from the WSEN-PADS sensor and humidity
-from the HTS221 sensor. Includes a startup calibration phase to compensate
-sensor offsets. Displays live temperature, humidity and pressure readings
-with horizontal progress bars and a comfort index on a round 128x128 OLED.
+from the HTS221 sensor. Displays live readings with a comfort index
+on the round 128x128 OLED using steami_screen widgets.
+
+Hardware:
+    - WSEN-PADS (temperature + pressure)
+    - HTS221 (humidity)
+    - SSD1327 128x128 OLED display (round)
 """
 
 from time import sleep_ms
 
 import ssd1327
 from hts221 import HTS221
 from machine import I2C, SPI, Pin
+from steami_screen import GRAY, GREEN, LIGHT, RED, WHITE, Screen, SSD1327Display
 from wsen_pads import WSEN_PADS
 
-# === Ecran ===
+# --- Display ---
 spi = SPI(1)
 dc = Pin("DATA_COMMAND_DISPLAY")
 res = Pin("RST_DISPLAY")
 cs = Pin("CS_DISPLAY")
-display = ssd1327.WS_OLED_128X128_SPI(spi, dc, res, cs)
+display = SSD1327Display(ssd1327.WS_OLED_128X128_SPI(spi, dc, res, cs))
+screen = Screen(display)
 
-# === Capteurs ===
+# --- Sensors ---
 i2c = I2C(1)
 pads = WSEN_PADS(i2c)
 hts = HTS221(i2c)
 
-# === Calibration ===
-print("Calibration en cours...")
-temps = []
-hums = []
-press = []
-for _ in range(10):
-    temps.append(pads.temperature())
-    hums.append(hts.humidity())
-    press.append(pads.pressure_hpa())
-    sleep_ms(200)
-
-OFFSET_TEMP = 20.0 - (sum(temps) / len(temps))
-OFFSET_HUM = 50.0 - (sum(hums) / len(hums))
-OFFSET_PRES = 1013.0 - (sum(press) / len(press))
-print(f"Offset T:{OFFSET_TEMP:.2f} H:{OFFSET_HUM:.2f} P:{OFFSET_PRES:.2f}")
-print("Calibration OK")
-
-
-# === Dessin ===
-def draw_hline(x, y, w, color=15):
-    for i in range(w):
-        display.pixel(x + i, y, color)
-
-
-def draw_vline(x, y, h, color=15):
-    for i in range(h):
-        display.pixel(x, y + i, color)
-
-
-def draw_rect(x, y, w, h, color=15):
-    draw_hline(x, y, w, color)
-    draw_hline(x, y + h - 1, w, color)
-    draw_vline(x, y, h, color)
-    draw_vline(x + w - 1, y, h, color)
-
-
-def draw_fill_rect(x, y, w, h, color=15):
-    for i in range(h):
-        draw_hline(x, y + i, w, color)
-
-
-def draw_circle(cx, cy, r, color=15):
-    x = r
-    y = 0
-    err = 0
-    while x >= y:
-        display.pixel(cx + x, cy + y, color)
-        display.pixel(cx + y, cy + x, color)
-        display.pixel(cx - y, cy + x, color)
-        display.pixel(cx - x, cy + y, color)
-        display.pixel(cx - x, cy - y, color)
-        display.pixel(cx - y, cy - x, color)
-        display.pixel(cx + y, cy - x, color)
-        display.pixel(cx + x, cy - y, color)
-        y += 1
-        err += 1 + 2 * y
-        if 2 * (err - x) + 1 > 0:
-            x -= 1
-            err += 1 - 2 * x
-
-
-def draw_bar_h(x, y, w, h, value, min_val, max_val, color=13):
-    draw_rect(x, y, w, h, 5)
-    ratio = (value - min_val) / (max_val - min_val)
-    ratio = max(0.0, min(1.0, ratio))
-    filled = int((w - 2) * ratio)
-    if filled > 0:
-        draw_fill_rect(x + 1, y + 1, filled, h - 2, color)
+# --- Comfort thresholds ---
+TEMP_MIN, TEMP_MAX = 18.0, 26.0
+HUM_MIN, HUM_MAX = 40.0, 60.0
+PRES_MIN, PRES_MAX = 1000.0, 1025.0
+
+POLL_MS = 1000
 
 
 def comfort_label(temp, hum, pres):
-    if 18 <= temp <= 26 and 40 <= hum <= 60 and 1000 <= pres <= 1025:
-        return "IDEAL", 15
-    elif temp > 30 or hum > 75:
-        return "CHAUD", 11
-    elif temp < 15 or hum < 25:
-        return "FROID", 9
-    elif pres < 1000:
-        return "BASSE P", 9
-    elif pres > 1025:
-        return "HAUTE P", 13
-    else:
-        return "CORRECT", 12
+    """Return a (label, color) tuple describing indoor comfort."""
+    if TEMP_MIN <= temp <= TEMP_MAX and HUM_MIN <= hum <= HUM_MAX and PRES_MIN <= pres <= PRES_MAX:
+        return "IDEAL", GREEN
+    if temp > 30 or hum > 75:
+        return "HOT", RED
+    if temp < 15 or hum < 25:
+        return "COLD", GRAY
+    if pres < PRES_MIN:
+        return "LOW P", GRAY
+    if pres > PRES_MAX:
+        return "HIGH P", LIGHT
+    return "OK", WHITE
 
 
 def draw_screen(temp, hum, pres):
-    display.fill(0)
-
-    # Bordure circulaire
-    draw_circle(64, 64, 62, 4)
-    draw_circle(64, 64, 60, 2)
-
-    # === TITRE ===
-    display.text("CLIMAT", 35, 20, 15)
-    draw_hline(19, 29, 90, 6)
-
-    # === TEMPERATURE ===
-    display.text("T", 19, 35, 7)
-    temp_str = f"{temp:.1f}C"
-    display.text(temp_str, 29, 35, 15)
-    draw_bar_h(19, 44, 90, 5, temp, 0, 50, 13)
-
-    # === HUMIDITE ===
-    display.text("H", 19, 52, 7)
-    hum_str = f"{hum:.1f}%"
-    display.text(hum_str, 29, 52, 15)
-    draw_bar_h(19, 61, 90, 5, hum, 0, 100, 11)
-
-    # === PRESSION ===
-    display.text("P", 19, 69, 7)
-    pres_str = f"{pres:.0f}hPa"
-    display.text(pres_str, 29, 69, 15)
-    draw_bar_h(19, 78, 90, 5, pres, 950, 1050, 10)
-
-    # === SEPARATEUR ===
-    draw_hline(19, 86, 90, 4)
-
-    # === CONFORT ===
-    label, c_color = comfort_label(temp, hum, pres)
-    cx = 64 - len(label) * 4
-    display.text(label, cx, 92, c_color)
-
-    # === CAPTEURS ===
-    draw_hline(19, 102, 90, 3)
-    display.text("PADS+HTS221", 22, 106, 4)
-
-    display.show()
-
-
-# === Boucle principale ===
-print("Station climatique demarree")
-while True:
-    try:
-        temp = pads.temperature() + OFFSET_TEMP
-        hum = hts.humidity() + OFFSET_HUM
-        pres = pads.pressure_hpa() + OFFSET_PRES
+    """Render one frame with all readings and comfort index."""
+    label, color = comfort_label(temp, hum, pres)
+
+    screen.clear()
+    screen.gauge(
+        int(temp), min_val=0, max_val=50, color=color,
+    )
+    screen.title("CLIMATE")
+    screen.value("{:.1f}".format(temp), unit="C")
+    screen.subtitle(
+        "H:{:.0f}%  P:{:.0f}hPa".format(hum, pres),
+        label,
+    )
+    screen.show()
+
+
+# --- Main loop ---
+print("Climate station started")
+print("Press Ctrl+C to exit.")
+
+try:
+    while True:
+        temp = pads.temperature()
+        hum = hts.humidity()
+        pres = pads.pressure_hpa()
         hum = max(0.0, min(100.0, hum))
-        print(f"T:{temp:.2f}C  H:{hum:.2f}%  P:{pres:.1f}hPa")
+        print("T:{:.1f}C  H:{:.1f}%  P:{:.0f}hPa".format(temp, hum, pres))
         draw_screen(temp, hum, pres)
-    except Exception as e:
-        print("Erreur:", e)
-        display.fill(0)
-        display.text("ERREUR", 35, 55, 15)
-        display.text(str(e)[:16], 0, 70, 9)
-        display.show()
-    sleep_ms(1000)
+        sleep_ms(POLL_MS)
+except KeyboardInterrupt:
+    print("\nClimate station stopped.")
+finally:
+    screen.clear()
+    screen.show()
+    pads.power_off()
+    hts.power_off()