data(smartphone): import 5000 PhoneDB raw variants

[Seungpyo1007]

Summary

• import 45 curated smartphone seed records from the Mobiles Dataset 2025 Kaggle CSV
• import 5,000 PhoneDB raw smartphone variant records from the mobile phones specs Kaggle CSV
• keep all newly imported records as verified: false for later TechEngine/manual audit
• refresh the published site/public/v1 smartphone indexes and detail JSON

Data sources

• https://www.kaggle.com/datasets/abdulmalik1518/mobiles-dataset-2025
• https://www.kaggle.com/datasets/sady36/mobile-phones-specs

Import notes

• this PR intentionally expands quantity using PhoneDB variant rows, including regional/model-code variants
• obvious tablet-like rows and validator-out-of-range rows were skipped
• fractional RAM values from PhoneDB were normalized upward to match TechEngine's integer response schema
• all imported records remain unverified until manual or TechEngine follow-up review

Verification

• python -m app.validate PASS
• python TechEngine\integrity_check.py data --strict PASS
• cd site && npm.cmd run build PASS
• git diff --check PASS

Closes #1