Describe the bug

docs/ats_compatibility.md#L105 states:

Typst supports PDF/UA-1 (the universal accessibility standard) and all conformance levels of PDF/A (the archival standard). These standards require proper Unicode text, embedded fonts, and a complete structure tree. A PDF that meets these standards is, by definition, machine-readable.

But RenderCV's own PDF output never actually targets PDF/UA-1 (or any PDF standard) — it just relies on Typst's default tagged-PDF output, which gets close but isn't the same thing. Running veraPDF's PDF/UA-1 (ua1) validation profile against a RenderCV-generated PDF (engineeringresumes theme) fails 2 of ~20,600 checks:

• ViewerPreferences.DisplayDocTitle not set on the document catalog (clause 7.1-10)
• No PDF/UA Identification XMP schema — the file never declares itself as PDF/UA-1 targeted at all (clause 5-1)

Every content/structure check passes (reading order, tags, headings, etc.), since Typst has produced tagged PDFs by default since v0.14 — the PDF is structurally almost there, it's just never told to actually target the standard.

To Reproduce

1. rendercv render <any-cv>.yaml (any theme)
2. Validate the output PDF against PDF/UA-1, e.g. with veraPDF: verapdf -f ua1 <output>.pdf
3. Observe FAIL, clauses 7.1-10 and 5-1

Root cause

src/rendercv/renderer/pdf_png.py#L42 (v2.8; unchanged on main, same call now at pdf_png.py#L43):

typst_compiler.compile(input=typst_path, format="pdf", output=pdf_path)

No pdf_standards argument is passed, even though the typst Python binding (and Typst's own --pdf-standard CLI flag) supports one directly.

Verified fix

Recompiling the same .typ output directly via typst.Compiler(...).compile(..., pdf_standards=["ua-1"]) (bypassing RenderCV) produces a PDF that passes veraPDF's ua1 profile with 0 failed checks — no template or CV content changes needed.

Suggested fix

Add an optional field to RenderCommand (schema/models/settings/render_command.py), e.g. pdf_standards: list[str] | None, threaded through to the compile() call in pdf_png.py.

Environment

RenderCV 2.8 (rendercv[full]), typst 0.15.0, Windows. Also reproduced on origin/main (1d4b87bc, 2026-03-25) — same call, unchanged.