add reverse proxy config documentation

[ptpu]

Hey, since I've been using Actual via Traefik for a few days now, I took the time to add a little bit to the documentation in that regard. I hope it fits so far. Please feel free to comment/improve anything.

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[github-advanced-security]

check-spelling found more than 10 potential problems in the proposed changes. Check the Files changed tab for more details.

[ptpu]

Where do i have to approve/add the unrecognized words?

[shall0pass]

The dictionary words to allow can either be placed in:

.github/actions/spelling/expect.txt

or

.github/actions/spelling/allow/keywords.txt

[github-actions]

@check-spelling-bot Report

🔴 Please review

See the 📂 files view, the 📜action log, or 📝 job summary for details.

❌ Errors	Count
❌ dictionary-not-found	4

See ❌ Event descriptions for more information.

Available 📚 dictionaries could cover words (expected and unrecognized) not in the 📘 dictionary

This includes both expected items (37) from .github/actions/spelling/expect.txt and unrecognized words (0)

Dictionary	Entries	Covers	Uniquely
cspell:typescript/dict/typescript.txt	1098	6	3
cspell:npm/dict/npm.txt	302	5	3
cspell:fullstack/dict/fullstack.txt	419	4	3
cspell:html/dict/html.txt	2060	7
cspell:css/dict/css.txt	263	6	1

Consider adding them (in .github/workflows/spelling.yml) for uses: check-spelling/check-spelling@main in its with:

      with:
        extra_dictionaries:
          cspell:typescript/dict/typescript.txt
          cspell:npm/dict/npm.txt
          cspell:fullstack/dict/fullstack.txt
          cspell:html/dict/html.txt
          cspell:css/dict/css.txt

To stop checking additional dictionaries, add (in .github/workflows/spelling.yml) for uses: check-spelling/check-spelling@main in its with:

check_extra_dictionaries: ''

[youngcw]

@shall0pass I cant tell why the test is failing. I think everything else looks good though.