What is the proper term for etching or digging of wall to hide conduit of cables
Solution 1:
It's called chasing. It took three goes to find this use in a dictionary to support this assertion.
a : to ornament (metal) by indenting with a hammer and tools without a cutting edge
b : to make by such indentation
c : to set with gems
a : groove, indent [q.v.]
b : to cut (a thread) with a chaser
— Merriam-Webster
Etymology from French enchâsser - to set (precious stone). It appears unconnected with chase meaning "to hunt etc", which is from the old French chacier later chascier by 11th century chaser. (OED) However a Northern French variant is written cacher, which is of course modern French for "to hide". One suspects there may be a connected root here. As we have noted before we are not authoritative on French etymologies.
Solution 2:
In the UK it is called chasing:
When running cables or pipes up (or along) a masonry wall, the neatest method is to bury (or, in builders terms, chase) them in the wall surface.
(From a DIY site)
Although this meaning doesn't appear in dictionaries I have checked, it probably derives from:
chase2: Engrave (metal, or a design on metal)
Edit: Just noticed that Merriam-Webster has this definition, which is closer:
2a : GROOVE, INDENT
b : to cut (a thread) with a chaser
Oxford Dictionary
I have also heard "channelled" used in this context.