agent: code-atomiser-fix — repair sed-scar provenance from 26c7307

The Magnotia->Lumotia rebrand commit 26c7307 ran a too-greedy
s/magnotia/lumotia/g across comments that already had the correct
legacy/target distinction. The commit author caught one case in
src-tauri/src/lib.rs ("magnotia era" -> "lumotia era" restored) but
missed four others, plus a duplicated word in a Cargo description
from an earlier two-name sed.

Fixed sites:
  * crates/storage/src/database.rs        — migrate_legacy_setting_keys docstring
  * src/lib/utils/localStorageMigration.ts — file-level docstring
  * src/lib/utils/settingsMigrations.ts    — historical-key comment
  * crates/cloud-providers/Cargo.toml      — description duplication
  * src-tauri/src/lib.rs                   — data-dir migration log + doc

None of the underlying code paths were wrong; the lies were
docstring-only. Risk: future maintainer reading any of these
comments at incident time could invert the migration direction or
conclude no migration ran.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/lib/utils/localStorageMigration.ts

@@ -1,11 +1,12 @@
 /**
- * Phase 7 of the lumotia -> lumotia rebrand cascade. Persisted UI state
+ * Phase 7 of the magnotia -> lumotia rebrand cascade. Persisted UI state
  * survives the rename via one-shot key migrations run at module-load
  * inside the stores that own each key.
  *
  * `migrateLocalStorageKey` is idempotent and crash-safe:
- *  - If the new key already exists, the old key (if any) is removed
- *    silently — the lumotia value is authoritative.
+ *  - If the new key already exists, the old (magnotia) key is removed
+ *    silently — the new (lumotia) value is authoritative; the legacy
+ *    (magnotia) key is removed.
  *  - If only the old key exists, its value is copied to the new key and
  *    the old key is removed.
  *  - If neither exists, this is a no-op.