Jev picks a Signal's icon, on the server's key, and each Signal counts its items (#263)

Jev chooses among options and cannot name one, so the page searches Font Awesome's index for each
word of the Signal's name, words and sentence, the best six each, and offers the likeliest 40.
POST /api/signals/icon asks a choice question on the server's TYPESAFE_KEY and answers with one
of those offered, never another. "Let Jev pick" in the icon picker, and a Signal made without an
icon gets one a moment after. Tried against TypeSafe: for AI Development, laptop-code 0.45 just
ahead of robot 0.40.

Each Signal's row says "12 items · 3 unread", as a feed's row counts its own, in place of its
words; /api/signals gives `items` beside `unread`, by the same rules as its list.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/ipx/CHANGELOG.md

@@ -14,7 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
-- Signals: a feed of your own, picked out of the noise of everything you subscribe to, holding the items TypeSafe's Jev says are about the subject you give it: a name, words, and a sentence of your own if they are not enough, from the last 30 days and every new one, judged on your own TypeSafe key, each with an icon of its own if you like (`/api/signals`, and `typesafe_key` on `/api/me`) (#254).
+- Signals: a feed of your own, picked out of the noise of everything you subscribe to, holding the items TypeSafe's Jev says are about the subject you give it: a name, words, and a sentence of your own if they are not enough, from the last 30 days and every new one, judged on your own TypeSafe key, each with an icon of its own if you like, which Jev can pick on the server's TypeSafe key (`POST /api/signals/icon`) (`/api/signals`, and `typesafe_key` on `/api/me`) (#254).
 
 ### Changed