review/update of read the docs documentation

[mschwamb]

review/update of read the docs documentation

[matthewholman]

Reopening: this was shut automatically when #478 merged, and it should not have been.

Why it happened. The commit message on 4e1b50f5 contains a sentence of the form "this does not #440, which is a broader review". GitHub's parser reads the closing keyword immediately before the issue number and ignores the negation wrapped around it, so the sentence saying the issue should stay open is what shut it. The pull request description had the same phrasing and was reworded before merge — the commit message was not, and keywords are honoured there too.

Worth knowing generally: writing about a closing keyword next to an issue number is enough to trigger it, in a PR body or a commit message.

What is genuinely done, and what is not.

#478 was a first pass: it replaced the LINCC template boilerplate with a real landing page — what Layup is, installation, a runnable quickstart, and navigation — and moved the contributor bootstrap to its own page. #479 separately fixed the docstrings that were rendering broken in the API reference (18 docutils warnings to 0).

Still open under this issue:

• The autoapi API reference has ~84 python_import_resolution warnings. Separate from the docstring formatting Fix the docstrings that render broken in the API reference (#440) #479 fixed; these are unresolved cross-module imports and they degrade the generated pages.
• The notebooks have not been reviewed. docs/notebooks/orbit_fitting_api.ipynb and the pre-executed visualizer demo predate most of this year's changes.
• The install instructions must change when the first release ships. The landing page currently warns readers off pip install layup, because that command installs a 1.3 kB placeholder. That warning becomes wrong the moment a real version is published, and the two need to move together.
• Log files land in the working directory with no way to redirect them. Raised in The log verb ships as a user-facing command, and every command litters the working directory #481 and not addressed by the change that shut it; worth deciding alongside LAYUP_CACHE_DIR (Make the default ephemeris/reference-data cache location configurable (currently ~/.cache, on the home partition) #448, PR Let LAYUP_CACHE_DIR set the default data location (#448) #484) rather than inventing a second mechanism.

Whoever picks this up should treat the landing page as done and start from the list above.