Astra review r6: settings-5-surfaces task 8 (tenant change resolves fresh)

Range 3e24809f..8837f20a.

Verdict: ACCEPT

Reviewed only git diff 3e24809f..8837f20a. I cannot run Go here; I ran no Go commands and modified no files.

r5 finding

N1 ADDRESSED. registry.go:1127 adds instr(col, char(0)) = 0. SQLite’s instr searches using the value’s byte length, so it detects embedded NULs without stopping at them. SQLite implementation

By inspection, the combined predicate accepts exactly 3–16 lowercase ASCII letters and maps every other account string to bab, matching controlname.ValidAccount and release.RouteAccount. The same expression applies to both stored and incoming accounts.

The tests pin the reported failure:

• updatesettings_test.go:160 adds seven SQL/Go equivalence cases covering leading, embedded, trailing and repeated NULs, including one after a 16-letter prefix.
• updatesettings_test.go:124 adds six upsert transitions, including "abc\x00x" ↔ "bab"; line 132 asserts that both settings columns survive.

These are regression cases, not exhaustive enumeration. The general equivalence follows from the predicate. “Fix round 2” reports red-before/green-after results; I have not independently reproduced them.

New findings in the fix diff

None found.

Out of scope

Changes outside 3e24809f..8837f20a, broader branch correctness, and landing gates.