in other words: Allow comments in the replay string

To match (pun intended) the naming convention in other places, keep
"match" for regular expressions matching.

Setting breakpoints in a debugger on select vsl events is tidious,
so add a simple facility to trigger abort() with a logexpect command.

Otherwise sanitizers suppressions may scroll the first expectation out.

Note to self: `process pNAME -winsz` is not documented.

TOSTRAND() creates a pointer with temporary lifetime which we must not
access outside of the expression where it is created.

Incidentally, this is what I had before a polish with good intentions,
which, as we all know, are not enough.

Noticed by Geoff, thank you

Ref ISO/IEC 9899:2018 §6.2.4 (8)
Ref 0c96fc65

Spotted by Coverity Scan.

Spotted by Coverity Scan.

Spotted by Coverity Scan: if we have a reservation, it must be the last
workspace allocation, so there must be one.

This plugs a leak spotted by Coverity Scan. It might be useful in other
places anyway, so it might as well be decoupled from constant regexp
parsing.

Refs #3776

Refs #3776

I somehow convinced myself that ${{ secrets.COVERITY_SCAN_TOKEN }} was
the default value.

It doesn't map the github repository name in our case.

> can not read an implicit mapping pair: a colon is missed

Courtesy of yamllint and the Github Actions web editor.

Better diff with the --ignore-all-space option.

got through all the initialization and is now ready to speak CLI.