tsbb login: leave out a forum this member cannot post in

[ralyodio]

tsbb 0.5.1 (profullstack/tsbb#17) returns canPost per forum, so a feed-only forum no longer has to announce itself with a 403 on the first release post.

The subtlety: which caller is asking

canPost is resolved for whoever asks, and the forum list read before the device flow is a guest's. A guest may post nowhere, so every canPost is false there — reading that as a refusal would reject a login that works.

Verified against the live board, same URL, one with a token and one without:

                 guest          member
announcements    canPost=false  canPost=true
news             canPost=false  canPost=false   <- feed-only, the real case
app-showcase     canPost=false  canPost=true
community        canPost=false  canPost=false   <- category

So the list is read twice

Before the flow, as a guest — only the checks that hold for everybody: an unknown slug, and a category (which holds forums, not topics). Both cost no device approval to refuse.

After the token arrives, as the member — canPost. A refused forum is dropped with a line saying why; only a selection with nothing postable left fails the login.

An older board omits the field, and undefined means "cannot tell" rather than "no", so every board before 0.5.1 behaves exactly as it did.

Verified

• bun x tsc --noEmit -p tsconfig.json clean; 320 tests pass, 0 fail (5 new).
• The new tests stub a board that answers differently with and without a token, and assert the member list is the one consulted, that an older board keeps every forum, and that a category is refused before device/start is ever called.
• Read live: bbs.hqtui.com says canPost=false for news and true for the other seven forums when asked with the connected member's token.

🤖 Generated with Claude Code

https://claude.ai/code/session_011XqFUXQkK6npCGxBtgizQg