feat: add 43 missing Selangor cities to Malaysia dataset

[dr5hn]

Rebased version of #1330 (data-only, no BQ.json/countries.json/schema.sql contamination). Adds 43 Selangor cities. Closes #1330

[github-actions]

CSC Validation Report

PR Format

• ✅ Description provided
• ❌ Data source linked
• ✅ Issue linked (recommended for data changes)
• ✅ Justification / context provided

Labels applied: data:cities

Schema Validation (223 records)

Errors (blocking):

• ❌ contributions/cities/MY.json: Record 1 ("Alor Gajah"): "id" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 1 ("Alor Gajah"): "created_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 1 ("Alor Gajah"): "updated_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 1 ("Alor Gajah"): "flag" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 2 ("Alor Setar"): "id" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 2 ("Alor Setar"): "created_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 2 ("Alor Setar"): "updated_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 2 ("Alor Setar"): "flag" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 3 ("Ampang"): "id" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 3 ("Ampang"): "created_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 3 ("Ampang"): "updated_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 3 ("Ampang"): "flag" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 4 ("Ayer Hangat"): "id" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 4 ("Ayer Hangat"): "created_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 4 ("Ayer Hangat"): "updated_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 4 ("Ayer Hangat"): "flag" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 5 ("Bagan Pulau Ketam"): "id" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 5 ("Bagan Pulau Ketam"): "created_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 5 ("Bagan Pulau Ketam"): "updated_at" must not be included (auto-managed)
• ❌ contributions/cities/MY.json: Record 5 ("Bagan Pulau Ketam"): "flag" must not be included (auto-managed)
• ...and 872 more errors

Warnings:

• ⚠️ contributions/cities/MY.json: Record 1 ("Alor Gajah"): unknown field "type"
• ⚠️ contributions/cities/MY.json: Record 1 ("Alor Gajah"): unknown field "level"
• ⚠️ contributions/cities/MY.json: Record 1 ("Alor Gajah"): unknown field "parent_id"
• ⚠️ contributions/cities/MY.json: Record 1 ("Alor Gajah"): unknown field "native"
• ⚠️ contributions/cities/MY.json: Record 1 ("Alor Gajah"): unknown field "population"
• ⚠️ contributions/cities/MY.json: Record 1 ("Alor Gajah"): unknown field "translations"
• ⚠️ contributions/cities/MY.json: Record 2 ("Alor Setar"): unknown field "type"
• ⚠️ contributions/cities/MY.json: Record 2 ("Alor Setar"): unknown field "level"
• ⚠️ contributions/cities/MY.json: Record 2 ("Alor Setar"): unknown field "parent_id"
• ⚠️ contributions/cities/MY.json: Record 2 ("Alor Setar"): unknown field "native"
• ...and 1328 more warnings

Cross-Reference Validation

✅ 446 reference(s) verified

Geo-Bounds Check

✅ All 223 coordinate(s) within expected country bounds

Duplicate Detection

• ⚠️ contributions/cities/MY.json: Record 1 ("Alor Gajah") appears to be a duplicate of existing "Alor Gajah" (id: 76409, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 2 ("Alor Setar") appears to be a duplicate of existing "Alor Setar" (id: 76410, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 3 ("Ampang") appears to be a duplicate of existing "Ampang" (id: 76411, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 4 ("Ayer Hangat") appears to be a duplicate of existing "Ayer Hangat" (id: 76412, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 5 ("Bagan Pulau Ketam") appears to be a duplicate of existing "Bagan Pulau Ketam" (id: 76413, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 6 ("Bagan Serai") appears to be a duplicate of existing "Bagan Serai" (id: 76414, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 7 ("Bahau") appears to be a duplicate of existing "Bahau" (id: 76415, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 8 ("Bakri") appears to be a duplicate of existing "Bakri" (id: 76416, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 9 ("Bandar Labuan") appears to be a duplicate of existing "Bandar Labuan" (id: 76417, distance: 0.0km)
• ⚠️ contributions/cities/MY.json: Record 10 ("Banting") appears to be a duplicate of existing "Banting" (id: 76418, distance: 0.0km)

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❌ 892 error(s), 1561 warning(s) | Status: Changes required

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