data(mobile): reclassify tablet watch and PDA records

[Seungpyo1007]

Summary

• reclassify existing mobile-source tablet records into data/tablet variant folders
• reclassify wearable records into data/watch variant folders
• reclassify PDA and handheld records into data/pda variant folders
• refresh public v1 static dump counts and list/detail JSON for tablets, watches, and pdas

Data changes

• tablets: +446 imported records, now 447 total
• watches: +77 imported records, now 78 total
• pdas: +109 imported records, now 110 total
• all imported records are verified: false and retain their original source_urls
• original data/smartphone records were not moved or deleted in this batch

Verification

• python -m app.validate: PASS
• python TechEngine\integrity_check.py data --strict: PASS (no hard anomalies; existing advisory outliers remain)
• cd site && npm.cmd run build: PASS
• git diff --check origin/main...HEAD: PASS

Notes

• This is a reclassification import from previously imported PhoneDB/Kaggle-style mobile sources.
• Variant folders use data////<base_model_slug>/<variant_slug>.json.
• PDA false positives from OPPO PDAM model numbers and TCL Palm Phone were excluded before commit.

Closes #1