docs: ArcadeDB — DATETIME_MICROS reported as #8090; the NULL BOOLEAN note is stale

[singhpratech]

Two ArcadeDB behaviours that had been documented but not filed are now settled, in opposite directions.

DATETIME_MICROS moves to Reported. A value written with a space separator and a fraction — the form psqlodbc renders a bound timestamp in — is stored as NULL while the INSERT reports success. ArcadeDB filed it themselves on 2026-09-21 as ArcadeData/arcadedb#8090, severity:critical, after the compatibility notes were shared with them, and their issue names the cause: a blanket catch in Type.convert() logs at FINE and returns null.

The NULL BOOLEAN note was stale and is corrected. It was observed on 26.8.1 on 2026-08-28. A project contributor had already filed the same behaviour as #6674 on 2026-08-24 and closed it the same day, and the fix shipped in 26.9.1 on 2026-09-03.

Retested here on 2026-09-21 against arcadedata/arcadedb:26.9.1, through psqlodbc 16 with BoolsAsChar=0 and then adbcBridge into Arrow:

• BOOLEAN arrives as Arrow bool; a NULL property and an absent property both come back as SQL NULL; true/false intact. Fixed.
• DATETIME_MICROS reproduces exactly as #8090, and a bound SQL_TYPE_TIMESTAMP parameter loses its value the same way, which is the client-side half of their server-side reproducer.

The compatibility entry keeps its not_null flag on the boolean column for now, because the matrix row still records 26.9; it moves when that row is re-measured. The scripts and the full output are kept under private/.