scons Manpage: modify the Builder Methods section

In clarifying the detail on when a builder's target can be deduced, it seemed like the concept of a single-source builder should be introduced in this context. So now those builders we know are single-source have that notation in their entry in this section. Also mentions that pseudo-Builders may have a different calling sequence.

A chunk of text about dependencies previously appeared after the listing of builder methods, where it would be hard to spot. Moved up into the text before the listing, and integrate in a bit more smoothly.

A couple of very minor typing things adjusted along the way - mainly using single_source consistently as a bool.

There are no functional changes, so no test impacts.

Contributor Checklist:

[ ] I have created a new test or updated the unit tests to cover the new/changed functionality.
[X] I have updated CHANGES.txt and RELEASE.txt (and read the README.rst).
[X] I have updated the appropriate documentation

Jan 03 '25 00:01 mwichmann

Grumble tried to update this, now CHANGES and RELEASE have reset for the 4.9 release, and github tells me "fatal: The upstream branch of your current branch does not match the name of your current branch." Dunno what that's about...

Mar 08 '25 16:03 mwichmann

Hmmm, I remember trying to attach the condensed text versions of the manpage output, but they don't seem to be in this issue. Trying again here:

man-new.txt man-old.txt

Mar 12 '25 13:03 mwichmann

I've marked this as "in progress" on the task board while I figure out what to do.

May 15 '25 16:05 mwichmann

Withdrawn. Will be resubmitted in smaller chunks as time permits.

Sep 09 '25 13:09 mwichmann