[sogav21]

Description

Part of #14822. Follow-up to #15199, as requested in the review.

Adds the three missing Greek translations so book sharing and download controls and the skip-to-content link no longer fall back to English.

tools-share: "Κοινοποίηση"
tools-download: "Λήψη"
skip-to-content: "Μετάβαση στο κύριο περιεχόμενο"

The sharing label refers to the book's social sharing menu. The download label matches the existing Greek notebook download labels. The skip-link wording matches the Greek wording in the gov.cy Design System.

Evidence

• Before: all three keys are absent from _language-el.yml; the controls fall back to English.
• After: UTF-8 YAML validation with duplicate-key rejection passes. Exactly these three keys were added, all 117 existing values are preserved, and the new keys exist in _language.yml.
• git diff --check passes.
• No Quarto render or full test suite was run: Quarto and Deno are not installed in this environment.

Checklist

I have (if applicable):

• referenced the GitHub issue this PR closes
• updated the appropriate changelog in the PR
• ensured the present test suite passes
• added new tests
• created a separate documentation PR in Quarto's website repo and linked it to this PR

Merge Danger

Door: two-way

Blast Radius: Greek labels

AI-assisted PR

• AI tool used: Codex
• Codebase grounding: local clone of current upstream main; English and Greek language files; book sharing/download consumers; skip-link implementation; Per-language _language-*.yml files have drifted from _language.yml #14822 and the review of Translate revealjs-menu-button-label in Greek #15199.
• Human review: The contributor reviewed and approved the three translations and the prepared change before submission. Automated checks performed by Codex are listed above; no human-executed render is claimed.

[posit-snyk-bot]

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