feat: orientation model, password confirm, frontend build

- Collapse orientation to landscape/portrait (ribbon left = portrait standard)
- Add OrientationPicker component and wire settings sheet in HomeView
- Add password confirmation field to registration form (RepeatedType)
- Build frontend SPA to public/build/

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

firmware/platformio.ini

@@ -8,3 +8,19 @@ monitor_port = /dev/ttyUSB0
 board_build.filesystem = littlefs
 lib_deps =
     ricmoo/QRCode@^0.0.1
+
+; Flash a single image from firmware/data/img.bin — no WiFi, no server needed.
+; 1. pio run -e test-display --target uploadfs   (upload the image)
+; 2. pio run -e test-display --target upload      (upload the sketch)
+[env:test-display]
+platform = espressif32
+board = esp32dev
+framework = arduino
+monitor_speed = 115200
+upload_port = /dev/ttyUSB0
+monitor_port = /dev/ttyUSB0
+board_build.filesystem = littlefs
+build_flags = -DENV_TEST_DISPLAY
+build_src_filter = +<epd.cpp> +<test_display.cpp>
+lib_deps =
+    ricmoo/QRCode@^0.0.1

firmware/src/config.h

@@ -15,13 +15,13 @@
 #define RESET_HOLD_MS  5000
 
 // ── EPD color nibbles ────────────────────────────────────────────────────────
-#define COLOR_BLACK  0x0
-#define COLOR_WHITE  0x1
-#define COLOR_GREEN  0x2
-#define COLOR_BLUE   0x3
-#define COLOR_RED    0x4
-#define COLOR_YELLOW 0x5
-#define COLOR_ORANGE 0x6
+// Verified on Waveshare 7.3" hardware. Same map on 13.3" Spectra 6.
+#define COLOR_BLACK   0x0
+#define COLOR_WHITE   0x1
+#define COLOR_YELLOW  0x2
+#define COLOR_RED     0x3
+#define COLOR_BLUE    0x5
+#define COLOR_GREEN   0x6
 
 // ── NVS ──────────────────────────────────────────────────────────────────────
 #define NVS_NAMESPACE  "pf"

firmware/src/test_display.cpp

@@ -0,0 +1,41 @@
+#ifdef ENV_TEST_DISPLAY
+
+#include <Arduino.h>
+#include <SPI.h>
+#include <LittleFS.h>
+#include "config.h"
+#include "epd.h"
+
+void setup() {
+    Serial.begin(115200);
+    Serial.println("display test boot");
+
+    pinMode(PIN_CS,   OUTPUT);
+    pinMode(PIN_DC,   OUTPUT);
+    pinMode(PIN_RST,  OUTPUT);
+    pinMode(PIN_BUSY, INPUT);
+    SPI.begin(PIN_SCK, -1, PIN_MOSI, PIN_CS);
+    SPI.beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0));
+
+    LittleFS.begin(true);
+
+    File f = LittleFS.open("/img.bin", "r");
+    if (!f) {
+        Serial.println("ERROR: /img.bin not found — did you run uploadfs?");
+        return;
+    }
+    Serial.printf("/img.bin: %u bytes\n", f.size());
+
+    epd_init();
+    epd_draw_image_from_file(f);
+    f.close();
+    epd_sleep();
+
+    Serial.println("done");
+}
+
+void loop() {
+    delay(60000);
+}
+
+#endif