fix(provisioning): two-QR flow — WiFi join + open-browser trigger

User report: iOS sees the captive network correctly (the captive UI
fires the moment any app makes an HTTP request), but won't auto-pop
it from a QR-scan join. This is recent-iOS hardening — Apple no
longer aggressively opens CNA on QR-initiated joins.

Workaround: a single QR can only encode one action, but two QRs
side-by-side close the loop —

  STEP 1 — WiFi-join QR (WIFI:T:WPA;S:NAME;P:pass;;)
           Phone joins PictureFrame.
  STEP 2 — URL QR (http://192.168.4.1/)
           Phone opens Safari → Safari hits 192.168.4.1 → that HTTP
           request is the "any app" trigger that fires the captive
           UI deterministically.

Implementation:
- WiFi QR shrinks from cell 5 (185 px) to cell 4 (148 px) to make
  room for the URL QR below.
- URL QR is static, baked into ap_bg.bin via Python qrcode at gen
  time — no firmware QR-render changes needed for it.
- epd_draw_ap_screen / _retry overlay coords updated to match the
  new WiFi QR position (581, 100, 4).
- Left-panel step list now reads "1. Unlock / 2. Scan QR 1 / 3. Scan
  QR 2 / 4. Enter password and tap Connect".

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/gen_screens.py

@@ -80,9 +80,12 @@ DIV2_X   = 508
 RIGHT_X  = 510; RIGHT_W = 290   # 800-510
 
 # QR positions (MUST match epd.cpp constants)
-AP_QR_CELL  = 5
+# WiFi-join QR — drawn at runtime by firmware. Cell shrunk from 5 to 4
+# (148 px instead of 185 px) to leave room for a second QR below it that
+# opens Safari → forces iOS captive UI.
+AP_QR_CELL  = 4
 AP_QR_MODS  = 37          # version 5, ECC_LOW
-AP_QR_PX    = AP_QR_MODS * AP_QR_CELL   # 185
+AP_QR_PX    = AP_QR_MODS * AP_QR_CELL   # 148
 
 SETUP_QR_CELL = 5
 SETUP_QR_MODS = 41        # version 6, ECC_LOW
@@ -92,9 +95,13 @@ SETUP_QR_PX   = SETUP_QR_MODS * SETUP_QR_CELL  # 205
 RIGHT_CX = RIGHT_X + RIGHT_W // 2   # 655
 BODY_CY  = BODY_Y + (H - BODY_Y) // 2  # 266
 
-AP_QR_X  = RIGHT_CX - AP_QR_PX  // 2   # 563
+# Stacked layout: WiFi QR (top) + URL QR (bottom). Each has a label
-AP_QR_Y  = BODY_CY  - AP_QR_PX  // 2   # 174  (will nudge down below label)
+# above it. AP_QR is dynamic — firmware overlays it at runtime. URL QR
-AP_QR_Y  = 185      # nudge down a bit for "SCAN TO CONNECT" label above
+# is static (always http://192.168.4.1/) and baked into the bg image.
+AP_QR_X     = RIGHT_CX - AP_QR_PX // 2   # centered horizontally
+AP_QR_Y     = 100                          # below STEP 1 label
+URL_QR_BOX  = 4                            # cell size in px
+URL_QR_TARGET_Y = 320                      # below STEP 2 label
 
 SETUP_QR_X = RIGHT_CX - SETUP_QR_PX // 2  # 553
 SETUP_QR_Y = BODY_CY  - SETUP_QR_PX // 2  # 164
@@ -213,15 +220,16 @@ def gen_ap(accent=YL, header="SETUP MODE  —  STEP 1 OF 2", qr_label="SCAN TO C
     bb = draw.textbbox((0,0), "WiFi", font=F_HEAD)
     draw.rectangle([28, BODY_Y+82, 28+bb[2]+2, BODY_Y+85], fill=accent)
 
-    # Steps — step 1 is the unlock-first prompt because iOS won't open
+    # Steps — step 1 is the unlock-first prompt (iOS won't fire the
-    # the captive portal from a locked-phone scan, and we'd rather
+    # captive UI from a locked-phone scan). Two-QR flow because iOS
-    # surface that requirement up front than have the user discover it
+    # in recent versions doesn't auto-open the captive portal even
-    # by scanning, getting nothing, and giving up.
+    # after CNA detects it; scanning the second QR opens Safari
+    # which forces the portal to render.
     steps = [
-        ("Unlock your phone first", ""),
+        ("Unlock your phone first",    ""),
-        ("Scan the QR code →",      "Phone joins PictureFrame-91F8"),
+        ("Scan QR 1 →",                "joins PictureFrame WiFi"),
-        ("Browser opens — enter",   "your home WiFi password"),
+        ("Scan QR 2 →",                "page opens in Safari"),
-        ("Tap Connect and watch",   "for the QR code to change"),
+        ("Enter your WiFi password",   "and tap Connect"),
     ]
     sy = BODY_Y + 95
     step_pitch = 38
@@ -261,22 +269,46 @@ def gen_ap(accent=YL, header="SETUP MODE  —  STEP 1 OF 2", qr_label="SCAN TO C
     orientation_diagrams(draw, accent, show_active_ls=True)
 
     # ── Right panel ──────────────────────────────────────────────
+    # Stacked: STEP 1 (WiFi join QR, dynamic) above STEP 2 (URL QR, static
+    # → http://192.168.4.1/, baked into bg). The URL QR is the trick that
+    # forces iOS to open the captive portal: scanning a URL QR launches
+    # Safari, Safari hits 192.168.4.1, iOS sees the request go to a
+    # captive network and renders the portal instead of fighting whether
+    # to auto-show CNA.
     cx = RIGHT_CX
-
-    # QR label — accent-colored on retry so the failure is unmistakable.
     label_color = accent if accent != YL else BK
-    text_center(draw, cx, AP_QR_Y - 26, qr_label, F_BIG, label_color)
 
-    # QR border: accent outer, black inner
+    # Step 1 — WiFi join (dynamic QR, overlaid by firmware)
+    text_center(draw, cx, AP_QR_Y - 22, "STEP 1  —  JOIN WIFI", F_BIG, label_color)
     qx, qy, qp = AP_QR_X, AP_QR_Y, AP_QR_PX
     draw.rectangle([qx-6, qy-6, qx+qp+5, qy+qp+5], outline=accent, width=3)
     draw.rectangle([qx-3, qy-3, qx+qp+2, qy+qp+2], outline=BK, width=3)
-
-    # Leave QR area white for firmware overlay
     leave_qr_white(draw, qx, qy, qp)
+    text_center(draw, cx, qy+qp+8, qr_label, F_FOOT, label_color)
 
-    # "Encodes WIFI:..." label below
+    # Step 2 — URL QR (static, baked here so we don't need a second
-    text_center(draw, cx, qy+qp+10, "WIFI:T:WPA;S:PictureFrame-91F8;P:pictureframe;;", F_FOOT, (100,100,95))
+    # firmware render path; URL is fixed at http://192.168.4.1/).
+    url_qr = qrcode.QRCode(
+        version=None,
+        error_correction=qrcode.constants.ERROR_CORRECT_L,
+        box_size=URL_QR_BOX,
+        border=2,
+    )
+    url_qr.add_data("http://" + "192.168.4.1" + "/")
+    url_qr.make(fit=True)
+    url_img = url_qr.make_image(fill_color=BK, back_color=WH).convert("RGB")
+    url_w, url_h = url_img.size
+    url_x = cx - url_w // 2
+    url_y = URL_QR_TARGET_Y
+
+    text_center(draw, cx, url_y - 22, "STEP 2  —  OPEN PAGE", F_BIG, label_color)
+    # Decorative border around the static URL QR — same accent treatment
+    # as the WiFi QR for visual consistency.
+    draw.rectangle([url_x-6, url_y-6, url_x+url_w+5, url_y+url_h+5], outline=accent, width=3)
+    draw.rectangle([url_x-3, url_y-3, url_x+url_w+2, url_y+url_h+2], outline=BK, width=3)
+    img.paste(url_img, (url_x, url_y))
+
+    text_center(draw, cx, url_y + url_h + 8, "http://192.168.4.1/", F_FOOT, label_color)
 
     return img
 

src/panels/waveshare73/v1/epd_driver.cpp

@@ -175,14 +175,14 @@ static void draw_from_lfs(const char* path, uint8_t fallback_color,
 }
 
 void epd_draw_ap_screen(QRCode* qr) {
-    // AP_QR_X=563, AP_QR_Y=185, AP_QR_CELL=5  (must match gen_screens.py)
+    // AP_QR_X=581, AP_QR_Y=100, AP_QR_CELL=4  (must match gen_screens.py)
-    draw_from_lfs("/ap_bg.bin", COLOR_YELLOW, qr, 563, 185, 5);
+    draw_from_lfs("/ap_bg.bin", COLOR_YELLOW, qr, 581, 100, 4);
 }
 
 void epd_draw_ap_screen_retry(QRCode* qr) {
     // Same QR coordinates — only the bg .bin differs (red accents,
     // "Connection Failed — try again" label).
-    draw_from_lfs("/ap_bg_retry.bin", COLOR_RED, qr, 563, 185, 5);
+    draw_from_lfs("/ap_bg_retry.bin", COLOR_RED, qr, 581, 100, 4);
 }
 
 void epd_draw_setup_screen(QRCode* qr) {