Add Heltec Capsule Sensor V3 document (#1299)

* Add Heltec Capsule Sensor V3 document

* Capsule Sensor document update

* Change the pics format of Capsule Sensor V3

* capsule sensor v3fix 20240701

docs/hardware/devices/heltec-sensor/buttons.mdx

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+---
+id: buttons
+title: Heltec Sensor Hardware Buttons
+sidebar_label: Buttons
+sidebar_position: 1
+---
+
+## Capsule Sensor V3
+
+  - **Long press 3 seconds:** Power on or shutdown.
+  - **Long press 8/16 seconds:** Long press for 8~16 seconds in the shutdown state until the blue indicator lights up. At this time, the device enters the WirelessBoot mode, which can be used to upload firmware.

docs/hardware/devices/heltec-sensor/index.mdx

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+---
+id: heltec-sensors
+title: Heltec® Plug&Play Sensors
+sidebar_label: HELTEC® Sensors
+sidebar_position: 7
+---
+
+import Tabs from "@theme/Tabs";
+import TabItem from "@theme/TabItem";
+
+<Tabs
+groupId="heltec"
+queryString="heltec"
+defaultValue="v3.0"
+values={[
+{label: 'Capsule V3.0', value: 'v3.0'}
+]}>
+<TabItem value="v3.0">
+
+## Heltec Capsule Sensor Rev. 3.0
+
+- **MCU:**
+  - ESP32-S3FN8 (WiFi & Bluetooth)
+- **LoRa Transceiver:**
+  - Semtech SX1262
+- **Frequency Options:**
+  - 433 MHz
+  - 470 - 510 MHz
+  - 863 - 870 MHz
+  - 902 - 928 MHz
+- **Connectors:**
+  - Magnetic suction interface
+  - Antenna:
+    - Dedicated 2.4 GHz SMT antenna for WiFi/Bluetooth
+    - Dedicated SMT antenna for LoRa
+
+### How to upload firmware
+
+:::info
+Capsule Sensor V3 uses WirelessBoot mode to upload firmware, exchange information, and print logs through WiFi.
+That is, whether you update the firmware locally or via the Web, You need to get the device into WirelssBoot state first. 
+:::
+Refer to this link for how to upload firmware for Capsule Sensor V3: [**Wireless Boot**](https://docs.heltec.org/en/node/esp32/capsule_sensor_v3/wireless_boot.html#).
+### Touch button/Physical button differences
+
+:::warning
+Because the touch button is easy to accidentally activate while close to metal or in your pocket, Heltec has discontinued production of this version. However, a small number of samples have entered the market.
+:::
+- Button differences
+![Capsule Sensor V3 Button](</img/hardware/heltec/capsule-sensor-v3-button.webp>)
+- Other hardware differences
+  1. Removal of [FDG6322C](https://www.mouser.com/datasheet/2/308/1/FDG6322C_D-2312203.pdf) (a dual N & P channel FET) from the physical-button version.
+  2. Antenna filter values physical-button version (L11 = 1.8pF, C15 = 2.7nH, C24 = 1.8pF) align more closely with ESP32-S3 reference design than touch-button version (L11 = 1.6nH, C15 = 6.9pF, C24 = 2.4pF).
+
+### Features
+- Meshtastic preinstalled.
+- Built-in battery.
+- Sensor replaceable.
+
+### Pin
+- Connector:
+  - Model name: [DF12NB(3.0)-10DS-0.5V(51)](https://resource.heltec.cn/download/Heltec%20Capsule%20Sensor%20V3/Connector.pdf) 
+  - Pin:
+    ![Capsule Sensor V3 pin](</img/hardware/heltec/capsule-connector.webp>)
+- More pin definitions please refer [Schematic Diagram](https://resource.heltec.cn/download/Heltec%20Capsule%20Sensor%20V3/Capsule_Main_Esp32_Schematic_Diagram.pdf)
+### Resources
+- Firmware file: `firmware-heltec_capsule_sensor_v3-X.X.X.xxxxxx.bin`
+- Purchase links
+  - International
+    - [Heltec](https://heltec.org/project/heltec-capsule-sensor-v3/)
+    - [AliExpress](https://www.aliexpress.us/item/3256805256690400.html)
+
+</TabItem>
+
+</Tabs>

docs/hardware/devices/heltec-sensor/peripherals.mdx

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+---
+id: peripherals
+title: Heltec Sensor Peripherals
+sidebar_label: Peripherals
+sidebar_position: 3
+---
+
+import Tabs from "@theme/Tabs";
+import TabItem from "@theme/TabItem";
+
+<Tabs
+groupId="heltec"
+queryString="heltec"
+defaultValue="capsule-sensor-v3"
+values={[
+{label: 'Capsule Sensor V3', value: 'capsule-sensor-v3'},
+]}>
+<TabItem value="capsule-sensor-v3">
+
+## Capsule Sensor V3
+
+### Introduction
+Strong extensibility is an important feature of Capsule Sensor V3. By replacing the sensor module at the bottom of the device, the device can be flexibly used in various occasions.
+
+:::warning
+Different sensors may require different firmware versions, and the current version is based on the GNSS version. We will update the other firmware as soon as possible.
+:::
+
+### Heltec sensor type
+:::info
+Each Capsule Sensor V3 comes with a sensor module by default when you buy it, you just need to choose it at the time of purchase. You can also purchase other sensors which is Capsule Sensor V3   from Heltec, and we will continue to expand the variety of these sensors.
+:::
+  - GNSS: [Quectel_L76K_V1](https://resource.heltec.cn/download/Heltec%20Capsule%20Sensor%20V3/Quectel_L76K_V1.1-1.pdf)
+  - Temperature&Humidity: [GXHTC3_EN_V2.4](https://heltec.org/project/temp-humi-sensor/)
+  - 3-Axis: [DA217](https://heltec.org/project/3-axis-acceleration-sensor/)
+  - Atmospheric pressure sensor: [BMP280](https://heltec.org/project/atmospheric-pressure-sensor/)
+
+### Sensor module replacement step
+![Capsule Sensor V3 Button](</img/hardware/heltec/capsule-sensor-extensibility.webp>)
+ 1. Shutdown of device.
+ 2. Remove the bottom screw of the device and remove the back cover.
+ 3. Gently remove the old module.
+ 4. Plug in the new sensors.
+ 5. Close the cap and return the screw. If the firmware is not compatible, download a new one.
+:::warning
+Be careful not to screw too hard, otherwise it will damage the plastic structure. Also note the direction of the charging interface.
+:::
+
+</TabItem>
+</Tabs>
+