interp: add new ini setting disabling auto reset to G54 on M2,M30

[Sigma1912]

As requested here:
https://forum.linuxcnc.org/38-general-linuxcnc-questions/58821-how-to-remove-automatic-g54-after-m2-m30#346816

Adds a new ini file setting to disable the automatic resetting of the current WCS to G54 on M2 and M30.

Setting defaults to '0' so this modification is opt-in and default behavior is unchanged.

[zz912]

Can I ask you add it in to pncconf?

here:

linuxcnc/src/emc/usr_intf/pncconf/build_INI.py

Line 235 in 1c36c76

add:

        print("# When DISABLE_AUTO_G54_ON_PROGSTOP = 1'", file=file)
        print("# M2,M30 and M99 will no longer'", file=file)
        print("# automatically reset the active WCS to 'G54'", file=file)
        print("DISABLE_AUTO_G54_ON_PROGSTOP = 0", file=file)

[zz912]

I tested main functionality of this PR in Gmoccapy. It works.

[Sigma1912]

@zz912
Added as requested (I made the comment a bit more compact)

[Sigma1912]

@zz912 could you please clarify whether your requested addition to pncconf was for gmoccapy only or for all guis

[zz912]

I want it for all GUIs. I made wrong numbers of spaces.
Thank you for check.

[andypugh]

I don't like "PROGSTOP".
Can you make it "DISABLE_AUTO_G54_ON_M2_M30 ?
(This makes it more explicit that a g-code file wrapped in "%" won't trigger the behaviour.)

[zz912]

I prefer "DISABLE_AUTO_G54".

[Sigma1912]

I don't like "PROGSTOP".
Can you make it "DISABLE_AUTO_G54_ON_M2_M30 ?
(This makes it more explicit that a g-code file wrapped in "%" won't trigger the behaviour.)

Yes, 'progstop' might indeed be a bit misleading. Note though that for a g-code file wrapped in "%" the WCS is not (and has never been) automatically switched to G54 so there isn't really much cause for confusion.

In this sense it might indeed be better to just make it "DISABLE_AUTO_G54" and leave the details to the documentation. Opinions?

[Sigma1912]

Changed to "DISABLE_AUTO_G54" for now. Happy to change again if preferred.
Also dropped the misleading reference to M99 as that does only apply to preview (ie outside of task).

PR topic and comment have also been updated.