execute store result block <shucker box coords> Items[0].LodestonePos.X int 1 run data get entity @p[<however you’re selecting the runner>] Pos[0]

execute store result block <shucker box coords> Items[0].LodestonePos.Y int 1 run data get entity @p[<however you’re selecting the runner>] Pos[1]

execute store result block <shucker box coords> Items[0].LodestonePos.Z int 1 run data get entity @p[<however you’re selecting the runner>] Pos[2]

execute store result block <shucker box coords> Items[0].LodestonePos.X int 1 run data get entity @p[<however you’re selecting the runner>] Pos[0]

# using the 'store' directive indicates you want to put a value somewhere
execute store 

# you want to store the value you get, not just whether-or-not it succeeds
result 

# you want to put the result into a TileEntity (aka Block Entity) like a chest or shulker box
block

#the location of the tile entity
0 0 0

# the NBT path of the tile entity you want to edit
Items[0].LodestonePos.X

# indicates the resulting value should be converted to type `int`
int

# the scale of the resulting value (just multiplication)
1

# you want to run a command to get a value
run

# the command that should return the desired value
data get entity @p[<however you’re selecting the runner>] 

execute store result block <shucker box coords> Items[0].tag.LodestonePos.X int 1 run data get entity @p[<however you’re selecting the runner>] Pos[0]

execute store result block <shucker box coords> Items[0].tag.LodestonePos.Y int 1 run data get entity @p[<however you’re selecting the runner>] Pos[1]

execute store result block <shucker box coords> Items[0].tag.LodestonePos.Z int 1 run data get entity @p[<however you’re selecting the runner>] Pos[2]

execute store result block <shucker box coords> Items[0].tag.LodestonePos.X int 1 run data get entity @p[<however you’re selecting the runner>] Pos[0]

# using the 'store' directive indicates you want to put a value somewhere
execute store 

# you want to store the value you get, not just whether-or-not it succeeds
result 

# you want to put the result into a TileEntity (aka Block Entity) like a chest or shulker box
block

#the location of the tile entity
0 0 0

# the NBT path of the tile entity you want to edit
Items[0].tag.LodestonePos.X

# indicates the resulting value should be converted to type `int`
int

# the scale of the resulting value (just multiplication)
1

# you want to run a command to get a value
run

# the command that should return the desired value
data get entity @p[<however you’re selecting the runner>] 

This is a great way to actually modify the item in the player’s inventory: How can I modify an item while it is inside the player's inventory?

As far as changing the compass NBT goes, this should suffice:

I’m on mobile so I can’t test this at the moment, but I hope it works for you!

Copying the item into the player's inventory

A great post has already been made regarding this: How can I modify an item while it is inside the player's inventory?

Setting the lodestone position

These should suffice:

Now, why does this work?

The player's Pos attribute is an array of doubles (high-precision decimal values), whereas the compass's LodestonePos is an Object with attributes X, Y, and Z, which are all ints (whole numbers between -2³¹ and 2³¹-1).
Why the developers decided to have different implementations of coordinates is beyond me, but what this means for us is that we have to make three seperate assignments; one for each axis.

First, we get the player's position

Let's use @p for simplicity

data get @p Pos

this will return something like [0d, 3.14d, 12345.678d], which is an array of the X, Y, and Z coordinates respectively.

data get @p Pos[0]

This is just the X coordinate

Now let's store a value into an item

Let's use 0 0 0 as the location of a shulker box with a single compass in it

execute store result block 0 0 0 Items[0].LodestonePos.X ...

This is accessing the X coordinate of the LodestonePos attribute of the first item in a shulker box at 0 0 0, presuming one exists.

breaking down the execute command

Now we have

execute store result block <shucker box coords> Items[0].LodestonePos.X int 1 run data get entity @p[<however you’re selecting the runner>] Pos[0]

which will store the player's x position into the lodestone compass's X attribute.

Let's look at it piece by piece

# using the 'store' directive indicates you want to put a value somewhere
execute store 

# you want to store the value you get, not just whether-or-not it succeeds
result 

# you want to put the result into a TileEntity (aka Block Entity) like a chest or shulker box
block

#the location of the tile entity
0 0 0

# the NBT path of the tile entity you want to edit
Items[0].LodestonePos.X

# indicates the resulting value should be converted to type `int`
int

# the scale of the resulting value (just multiplication)
1

# you want to run a command to get a value
run

# the command that should return the desired value
data get entity @p[<however you’re selecting the runner>] 

Making it work for X, Y, and Z

This is relatively simple. Just replace Pos[0] with Pos[1] for the Y-coodinate, or Pos[2] for the Z-coordinate. Then Replace LodestonePos.X with LodestonePos.Y and LodestonePos.Z, and there you have the 3 different commands