Improve DFU and Erase Workflow in Flash Firmware Documentation

[rcarteraz]

Issue Summary

The current documentation instructs users to open the flash menu first to access the Enter DFU Mode button. However, since the recommended first step is to erase the firmware, users can instead start with the erase page (trash icon), which also provides an Enter DFU Mode button.

Section:
https://wiki.seeedstudio.com/sensecap_t1000_e/#step-1-enter-dfu-mode

Proposal

• Update the documentation to direct users to the erase page first.
• Show how to enter DFU mode from the erase page instead of the flash menu.
• Keep the existing tabbed layout for entering DFU mode (since some users may need the manual method).
• Clarify that immediately after flashing the erase.uf2 file, when clicking "Open Serial Monitor" and being prompted to select a device, the device will temporarily appear as "Xiao nRF52840"—this is the correct selection to complete the erase process.
• Note that after completing the erase process, the device automatically reboots back into DFU mode.
• Point out that after this, users can simply click "Return to Flasher", then click "Flash" to proceed with downloading the firmware uf2 file for drag-and-drop flashing.

[github-actions]

👋 @rcarteraz

Thank you for raising an issue. We will investigate into the matter and get back to you as soon as possible.
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[Jessie219-web]

thanks for your sharing! we will update the wiki later