Fix topic low-weight inactive topic weight vulnerability

[xmariachi]

Purpose of Changes and their Description

• Fix vulnerability: if topic has not been (re)activated, then the topic weights should not change.
• Change isAdded, error for just error on addTopicToActiveSetRespectingLimitsWithoutMinWeightReset, adding some error types. The flag was not really adding value, while not processing the flag would lead to a vulnerability like the one found.

Link(s) to Ticket(s) or Issue(s) resolved by this PR

Are these changes tested and documented?

• If tested, please describe how. If not, why tests are not needed. -- existing unit tests
• If documented, please describe where. If not, describe why docs are not needed. -- no need, changes in functions not user-facing.
• Added to Unreleased section of CHANGELOG.md?