feat: add Belgium and Portugal cross-border corridors — #40 PR 4/4

[HirenGajjar]

Part 4 of 4 for issue #40. Completes the cross-border corridor infrastructure with Belgium and Portugal.

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Context

This PR adds the two remaining corridors:

• Belgium — ~50,000 daily frontaliers, third largest corridor
• Portugal — ~100,000 residents, the largest foreign national community in Luxembourg

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Files added

data/sources/be/belgium-be-deces.yaml

URL verified: https://www.belgium.be/fr/famille/deces — loads correctly, title confirmed as "Décès".

• source_type: government_portal
• verification_status: source-checked
• languages: [fr, nl, de] — belgium.be is trilingual
• Includes title_fr, title_de, description_fr, description_de

Key facts documented in notes (from issue #40 research):

• Death must be declared to the municipality where the person died, usually handled by the undertaker
• Death certificate is then forwarded to the municipality of last residence
• Succession duties in Belgium are regional and depend on fiscal residence

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data/institutions/be/sfp.yaml

URL verified: https://www.sfpd.fgov.be — loads correctly as "Federal Pensions Service".

• id: institution:be:sfp
• verification_status: structured-from-source
• languages: [fr, nl, de] — Belgian trilingual institution (SFP in French, FPD in Dutch)
• References source:be:belgium-be-deces

Key facts documented in notes:

• Survivor pension applications submitted via mypension.be
• Coordinates with CNAP via EU social security coordination for cross-border cases
• Covers ~50,000 Belgian frontaliers

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data/scenarios/corridor-lu-be.yaml

• scenario_type: corridor
• countries: [LU, BE]
• publication_status: draft
• References all 5 PR1 conditions and both EU sources + BE source

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data/sources/pt/gov-pt-obito.yaml

URL: https://eportugal.gov.pt/en/temas/familia/morte — identified from official ePortugal portal structure; page was inaccessible during creation.

• source_type: government_portal
• verification_status: discovered — honest status, URL could not be confirmed loading
• last_verified_at: null
• Notes explicitly state full content verification requires further access

Key facts encoded from issue #40 research:

• Death of a Portuguese citizen abroad must be declared in Portugal
• Survivor pension (pensão de sobrevivência) requires minimum 36 months of contributions
• Application via Segurança Social Direta using form RP 5075

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data/institutions/pt/seguranca-social.yaml

URL: https://www.seg-social.pt — confirmed loading from research.

• id: institution:pt:seguranca-social
• verification_status: discovered — consistent with PT source status
• languages: [pt]

Key facts documented in notes:

• Portugal has the largest foreign national community in Luxembourg (~100,000 residents)
• 36-month contribution requirement for survivor pension
• Death of Portuguese national abroad must be registered in Portugal via consular services
• Centro Nacional de Pensões (CNP) within ISS handles international pension coordination

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data/scenarios/corridor-lu-pt.yaml

• scenario_type: corridor
• countries: [LU, PT]
• publication_status: draft
• Notes explicitly flag that further source verification is needed for full PT corridor detail

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Verification status honesty

Belgium sources are source-checked — URLs verified loading, content confirmed.
Portugal sources are discovered — URL identified from official portal structure but could not be verified loading during creation. This is consistent with issue #40's own note: "Detailed survivor-pension routing and death transcription process need further verification."

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Issue #40 complete

With this PR all four corridors are now in main:

• PR 1/4 (feat: add EU source records and cross-border conditions — #40 PR 1/4 (foundation) #47) — EU foundation (conditions + EU regulations) ✅
• PR 2/4 (feat: add Luxembourg–France cross-border corridor — #40 PR 2/4 #48) — France corridor ✅
• PR 3/4 (feat: add Luxembourg–Germany cross-border corridor — #40 PR 3/4 #49) — Germany corridor ✅
• PR 4/4 (this PR) — Belgium + Portugal corridors

Total new files across all 4 PRs: 25 files covering 2 EU regulations, 5 cross-border conditions, 4 corridor scenarios, 6 foreign sources, 5 foreign institutions.

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Schema compliance

• All schemas read before writing — additionalProperties: false respected throughout
• All condition IDs reference conditions from PR 1 (merged)
• All EU source IDs reference sources from PR 1 (merged)
• institution_ids and source_ids cross-references consistent within each PR

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Verified

• python3 scripts/validate.py — passes (34 data files, up from 28)
• All 6 trailing newlines confirmed 0a
• 6 new files, 0 existing files modified
• git status confirmed no unintended changes

[TommiLindfors]

Hi Hiren! 🎉🎉🎉

This is a wonderful milestone - with this final PR, all four cross-border corridors from issue #40 are now complete!

The Belgium + Portugal corridor work is excellent. A few highlights:

• Honest verification levels: Portugal correctly marked as discovered throughout, with last_verified_at: null on the ePortugal source since full content verification isn't done yet. Belgium's �elgium.be source properly marked source-checked. This kind of integrity in verification status is exactly what we need for trust.
• Trilingual Belgium descriptions: Including EN, FR, and DE descriptions on the Belgian source - and correctly listing all three Belgian official languages (r,
  l, de) - shows real attention to the linguistic complexity of cross-border work.
• Portuguese community context: The ~100,000 residents stat and the specific form reference (RP 5075 via Segurança Social Direta) are the kind of concrete details that will help families.
• Issue #41 linkage: The Portugal scenario notes correctly point to the source URL verification issue for further enrichment.

Schema validation passes. Merging now.

Recap of the full #40 series you delivered:

1. PR #47 - Foundation (EU sources + conditions) ✅
2. PR #48 - Luxembourg-France corridor ✅
3. PR #49 - Luxembourg-Germany corridor ✅
4. PR #50 - Luxembourg-Belgium + Portugal corridors ✅

This is an extraordinary contribution to the project - 4 PRs, 4 corridors, 6 new files in this PR alone. Thank you so much for your sustained dedication to Clarvia! 🚀

If you're looking for your next challenge, issue #41 (verifying 10 cross-border source URLs) would be a natural follow-up, and issue #22 (test cases for the validation script) is another good option.