[Lucrona]

Summary

• Treat empty and whitespace-only Blizzard names and gender as missing; preserve saved class, race, gender and specialization when metadata is absent.
• Accept only positive, representable levels and positive new Battle.net IDs. Existing non-NULL Battle.net IDs remain immutable.
• Keep the write set limited to card metadata and refresh timestamps; no changes to hours, sessions, uploads, verification, ownership, visibility, guild or media caches.

Regression coverage

• Separate Retail and Forever integration tests cover missing, NULL, empty, ASCII-whitespace and Unicode-whitespace metadata, localized names, zero/negative/overflow levels, immutable IDs, valid updates and older login timestamps.
• Full-row snapshots preserve all unrelated character fields; related snapshots preserve /played history, hours, sessions and cached guild/avatar/media.

Validation

• CI run 43089661255: both Linux and Windows jobs succeeded, verified at head 8da63578e41162e66428f54b8f3aa540a21876a3.
• CI passed formatting, whole-workspace clippy with -D warnings, whole-workspace tests, UI regression tests and the simulation smoke run.
• Local cargo fmt --all -- --check: passed.
• Local UI regression tests: 34 passed.
• Local server/core/sync clippy with -D warnings: passed.
• Local server/core/sync tests: 350 passed, 0 failed, 3 ignored, including both new Retail and Forever integration tests. Used a freshly initialized, isolated local PostgreSQL cluster, now stopped; no user data.
• Full local workspace clippy/tests were attempted but could not build desktop dependencies because pkg-config/GTK/WebKit are absent and the package mirror is blocked. The full workspace checks subsequently passed in CI.

Complete refresh write set

• bnet_level: positive i32 only; missing, zero, negative or overflow preserves saved value.
• bnet_last_login: valid integer-millisecond timestamp only; missing/invalid preserves, greatest prevents regression.
• class: trimmed nonblank name, normalized to uppercase ASCII letters; empty result becomes NULL, coalesce preserves saved value.
• race: trimmed nonblank name (plain or en_US), capped at 40 characters; missing/blank preserves.
• gender: trimmed nonblank type, lowercased; missing/blank preserves.
• bnet_spec: same guarded name handling as race; missing/blank preserves.
• faction: exact Blizzard stable HORDE/ALLIANCE enum only; missing/blank/unknown preserves.
• bnet_id: existing non-NULL ID always wins; only a positive integer can fill NULL.
• bnet_checked_at: set to now() as the refresh bookkeeping timestamp.

Guild/avatar/media are not written by this function. No migration, merge, deployment or live server access. No user data touched.