feat: verify Luxembourg Guichet source URLs and update titles

[HirenGajjar]

Closes #16

Visited both source URLs in a browser and verified they load correctly. Updated accessed_at, last_verified_at, and verification_status on both files.

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Findings

data/sources/lu/guichet-death-life-event.yaml

• ✅ URL loads correctly
• ⚠️ Title mismatch found — file had "Death of a close relative" but the current page title is "Dealing with the death of a loved one". Updated to match.
• verification_status: discovered → source-checked
• accessed_at: 2026-05-14 → 2026-05-27
• last_verified_at: null → 2026-05-27

data/sources/lu/guichet-death-certificate.yaml

• ✅ URL loads correctly
• ✅ Title matches — "Death certificate"
• verification_status: discovered → source-checked
• accessed_at: 2026-05-25 → 2026-05-27
• last_verified_at: null → 2026-05-27

---

Verified

• python3 scripts/validate.py — passes (10 data files)
• Trailing newlines present on both files
• 2 files changed, 13 insertions, 13 deletions

[TommiLindfors]

Merged! Good catch on the title change @HirenGajjar — the Guichet page has been updated from 'Death of a close relative' to 'Dealing with the death of a loved one', and catching that drift is exactly what source verification is for. This is the kind of proactive quality work that keeps the data trustworthy. Eight merged PRs.