I managed to get a Particle Electron into a state which I cannot seem to recover from. As shown in the photo below, the D7 led is constantly dimly lit.
I know the 0.7.0-rc1 firmware is supposed to prevent this from happening but I doubt you were running that unless you have the Particle CLI software installed. Do you?
If you do then the next step is to try to flash new firmware to the Electron via the Particle CLI software when the Electron is in DFU “Yellow Flashing LED” Mode. If you can get the Electron into DFU mode.
You get into DFU mode by holding down the Mode button and then hitting the REST button and while holding the Mode button until you see it flashing Yellow. It will flash magenta first, then yellow.
If you can’t get into DFU mode with the flashing Yellow then I think your only hope is trying a JTAG programmer and I have never used one of those before so can’t be of much help beyond this.