Trim both sides when comparing room/group names

A messaging adapter was emitting group titles with trailing whitespace while the user-facing settings UI stored the trimmed form. A case-insensitive equality check missed for 5+ days. Symptom looked like the whole feature was broken; the diff was one Unicode space character. Always normalize whitespace on BOTH sides of any user-vs-platform identifier compare, and add a regression test with the literal value from prod (not a synthetic).