WS connection pill flickers wider with "· NB queued" on every paste or fast typing burst #638

Bug

The WS pill in front of the CPU and memory gauges randomly grows to the right with · 12B queued and shrinks back, shifting the gauges next to it.

Steps to reproduce

1. Open a session and paste some text, commit IME input, or type a fast word.
2. Watch the WS pill: it briefly shows · NB queued, then shrinks back.

Cause

_computeConnectionDescriptor annotates the pill whenever more than 4 bytes are pending. A paste, IME commit or fast word is a few dozen bytes for a few milliseconds until its ACK lands, so every burst widens the pill. The 4-byte threshold stops a single keystroke flashing but does not account for bursts.

Status

Fixed, with tests, on branch fix/connection-indicator-flicker in my fork. Not submitted as a PR yet: I'm at the open-PR limit and the fix is queued behind my current open PRs (#567, #592, #616, #617, #618). I'll open the PR as soon as a slot frees, or sooner if you'd like to lift the limit or take it directly from the branch.