docs: fill missing guides and organize documentation

[krowvin]

Changes

• Add concise USGS, SHEF configuration, time-series loading, and troubleshooting guides to fill gaps found against the command tree.
• Organize navigation by setup, transfers, management, reference, and development; preserve existing page URLs and add a workflow index.
• Correct stale SHEF and user-role examples, document optional dependencies and PowerShell setup, and fix the README measurement import.
• Register new command guides in ownership metadata and regenerate maintainer notes/CODEOWNERS.

Testing

• Strict Sphinx HTML build (python -m sphinx -nW -E -b html docs docs/_build/html): passed.
• Sphinx linkcheck: passed with the repository's existing ignore rules.
• Local parser audit: 28 documented command snippets accepted without invoking callbacks; generated guide navigation and markup checked.
• Ownership metadata unit tests: 2 passed; generator check and git diff --check passed.
• Documentation-only change; no live CDA/USGS writes or transfer integration tests performed.

[krowvin]

Adding some extra thoughts in. Thanks to @msweier for bringing up the docs need some love!

[krowvin]

We might want a note that the login command does not work on the T7. It can't launch the local browser for the redirect it seems.

[krowvin]

Having names on files is new. This means our names will also show up in SEO(?) While it is useful to know when a doc file is changed I'm not so sure we should take the step into publishing our names on the doc site.

Something in saying everyone is responsible for complete, legible, and updated docs.

@msweier thoughts?

[krowvin]

@Enovotny

[krowvin]

Does this fit better in a dedicated block about virtual environments instead of assuming everyone will have a venv? Venv is still an advanced topic depending on the target audience.