Customizable XY optical endstop frame mount for Creality Ender-7

This moves the X endstop to the frame using an optical endstop

Klipper configuration changes
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Maximum X travel is ~262mm
Maximum Y travel is ~255mm
X Endstop has moved from left to right

- Change X endstop position from 0 to 262
- Change homing sequence: First home Y, then home X. Also make sure that individual homing of X is not possible when Y is not homed!
- Change configuration to home X axis twice to make sure homing coordinates are not wrongly offset to the right when the toolhead has been manually moved further to the right

printer.cfg:
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[stepper_x]
position_endstop: 262
homing_retract_dist: 15

[stepper_y]
position_endstop: 255

[homing_override]
axes: xyz
set_position_z: 0
gcode:
 G1 Z3 F900
 G28 Y
 G28 X
 G1 X163 Y136 F6000
 G28 Z

TEST CAREFULLY, MAKE SURE YOU DON'T RUN YOUR TOOLHEAD INTO SOMETHING!