docs: add WireView Pro II setup guide, note one-time host setup in README

The device is not usable out of the box on Linux: without the udev rule
the port is root:uucp 0660 with no stable name, and ModemManager probes
it for ~30 s after every plug. New docs/WireView.md covers the one-time
setup (udev rule, dialout group, port access, verification,
troubleshooting); README links to it from the feature note and the
documentation list.

docs/WireView.md

@@ -0,0 +1,112 @@
+# WireView Pro II Setup
+
+NVCurve reads the [Thermal Grizzly WireView Pro II](https://www.thermal-grizzly.com/en/wireview-pro-ii-gpu/s-tg-wv-p2) (12 VHPWR connector monitor) directly over its USB CDC/ACM serial port — **no exporter, no GUI, no kernel module required**.
+
+Before the first use, the host needs a one-time setup: a udev rule so the serial port is accessible under a stable name and left alone by other tools. After that, NVCurve auto-detects the device over USB — the WireView tab appears while the device is connected and disappears when it is unplugged.
+
+## Why a one-time setup is needed
+
+The WireView is an STM32 CDC/ACM virtual serial port (VID `0483`, PID `5740`). Out of the box, Linux:
+
+- creates the port as `root:uucp 0660` with no stable device name, and
+- lets **ModemManager** probe every new CDC-ACM port with AT/QCDM commands for up to ~30 s after each plug — it holds the port open and sends bytes the device does not expect.
+
+The udev rule below fixes both: the node becomes `root:dialout 0660`, a stable `/dev/wireview-pro2` symlink is created, and ModemManager is told to ignore the device.
+
+## 1. Install the udev rule
+
+```sh
+sudo tee /etc/udev/rules.d/99-wireview.rules > /dev/null <<'EOF'
+# WireView Pro II udev rules
+#
+# Same access policy as wireview-hwmon's 99-wireview-hwmon.rules: the node is
+# 0660 root:dialout, and the user logged in at the local seat gets an ACL via
+# uaccess. systemd applies that tag on hotplug from 73-seat-late.rules, which
+# runs before this 99- file and so never sees it, so each rule also runs the
+# uaccess builtin itself. The tag is still needed: logind uses it to move the
+# ACL to the new active session on a user switch.
+
+ACTION=="remove", GOTO="wireview_end"
+
+# Normal operation (STM32 CDC/ACM virtual serial port)
+SUBSYSTEM=="tty", ATTRS{idVendor}=="0483", ATTRS{idProduct}=="5740", GROUP="dialout", MODE="0660", TAG+="uaccess", RUN{builtin}+="uaccess", SYMLINK+="wireview-pro2"
+
+# Keep ModemManager away: it probes every new CDC-ACM port with AT and QCDM
+# commands for about half a minute, holding the port and sending the device
+# bytes it does not expect.
+SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="0483", ATTR{idProduct}=="5740", ENV{ID_MM_DEVICE_IGNORE}="1"
+SUBSYSTEM=="tty", ATTRS{idVendor}=="0483", ATTRS{idProduct}=="5740", ENV{ID_MM_PORT_IGNORE}="1"
+
+# DFU bootloader mode (firmware update)
+SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="0483", ATTR{idProduct}=="df11", GROUP="dialout", MODE="0660", TAG+="uaccess", RUN{builtin}+="uaccess"
+
+LABEL="wireview_end"
+EOF
+```
+
+> [!WARNING]
+> The rule sets `GROUP="dialout"`. If the `dialout` group does not exist on your distro, udev silently ignores the rule (the node stays `root:uucp`). Create it first: `sudo groupadd dialout`.
+
+Then reload the rules and apply them to an already-plugged device (a reload alone only affects future hotplugs):
+
+```sh
+sudo udevadm control --reload-rules
+sudo udevadm trigger
+```
+
+## 2. Port access
+
+- **NVCurve web server (systemd):** runs as root, so it can open the port as soon as the rule is in place — nothing else to do.
+- **CLI as a regular user:** add your user to the `dialout` group, then log out/in:
+
+  ```sh
+  sudo usermod -aG dialout $USER
+  ```
+
+  A running process only picks up new groups after a re-login; `sg dialout -c 'nvcurve ...'` works for a one-off.
+
+## 3. Verify
+
+```sh
+lsusb | grep 0483              # 0483:5740 present
+ls -l /dev/wireview-pro2       # -> /dev/ttyACM0
+```
+
+With the device plugged in, start (or restart) the NVCurve server. The **WireView** tab appears in the web UI and `GET /api/wireview` returns the device info and live samples. The tab disappears when the device is unplugged and reappears on re-plug — no restart needed.
+
+## Alternative: wireview-hwmon kernel module
+
+If the official `wireview-hwmon` kernel module and its `wireviewd` daemon are installed, the daemon owns the serial port and NVCurve automatically reads the sysfs node instead. No udev rule is needed in that case.
+
+## USB device IDs
+
+| Mode | VID | PID | Description |
+| --- | --- | --- | --- |
+| Normal | `0483` | `5740` | STM32 CDC/ACM virtual serial port |
+| DFU bootloader | `0483` | `df11` | STM32 bootloader (firmware updates only) |
+
+## Troubleshooting
+
+### WireView tab does not appear
+
+- `lsusb | grep 0483` — is the device visible at all (cable, USB port)?
+- `ls -l /dev/wireview-pro2` — if the node is `root:uucp`, the `dialout` group is missing or the rule did not load: `sudo groupadd dialout && sudo udevadm control --reload-rules && sudo udevadm trigger`.
+- Restart the NVCurve server — detection runs at startup, and the watchdog re-checks periodically afterwards.
+
+### `Permission denied` on the port (CLI)
+
+The user must be in the `dialout` group; a running process only picks up new groups after a restart/re-login.
+
+### Device visible but never connects
+
+The firmware occasionally stops answering the RTS welcome handshake (observed after USB state changes, e.g. udev re-triggers or boot) while still answering every data command. NVCurve falls back to the vendor-data reply and retries, but if it still does not connect, reset the USB device — physically unplug/replug, or without reaching for it:
+
+```sh
+P=$(readlink -f /sys/class/tty/ttyACM0)
+DEV=$(dirname "$(dirname "$(dirname "$(dirname "$P")")")")
+sudo bash -c "echo 0 > $DEV/authorized; sleep 1; echo 1 > $DEV/authorized"
+```
+
+---
+
+*The udev rule is taken from the wireview-reporter project, which uses the same access policy as the official `wireview-hwmon` module.*