Say which half of the wait a llama turn is in

A turn has two waits in front of the first token and they were one word.
`SessionStatus::Loading` was already the model coming off disk; this adds
`SessionStatus::Reading` for llama-server processing the prompt -- emitted when
the request goes out, cleared by the first thing the model says of any kind, so
it covers every generate in a tool loop rather than only the first.

Prefill is the expensive half on this machine: measured 9.5s for 6,068 tokens
and 22s for 14,068 on the 27B with the GPU to itself. Reported as `running`
that was indistinguishable from a model thinking, which is the thing the reader
is waiting for. The phone draws both with the working spinner and its own
words -- "loading model" and "reading prompt" -- and the session screen's
status row now spins for all three busy states instead of only `running`,
which is also how `loading` stops being a bare word with nothing moving.

Measured while checking the tok/s figure, and recorded in the rigs skill: the
27B holds 55.5 to 50.3 tok/s between 1.5k and 14k of context, so decode decays
gently, while the 0.6B on the CPU falls 30.1 to 11.5 over 6k. A shared GPU is a
different failure -- the model does not load at all.

Verified on the emulator against a real llama session: "loading model" while
the server started, then "reading prompt" with the spinner through prompt
processing, then the thinking card.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

PLAN.md

@@ -155,7 +155,14 @@ seq N", so there is no separate history path to drift from the live one.
 - `Answered { id, answer }` — so a question card resolves on every connected
   device, not just the one that answered.
 - `Status { state }` — idle / running / awaiting-input / compacting /
-  **waiting** / exited / unknown. `waiting` (2026-09-06) is the session's own
+  **loading** / **reading** / **waiting** / exited / unknown. `loading` is a
+  process that is up and cannot be spoken to yet (a model coming off disk);
+  `reading` (2026-09-19) is the model holding the prompt and not yet
+  answering, which on a long conversation is tens of seconds -- measured at
+  9.5s for 6,068 tokens and 22s for 14,068 on the 27B here. Reported as
+  `running` that was indistinguishable from a model thinking, which is the
+  thing the reader is actually waiting for. Both are working states: nothing
+  settles and nothing is invited. `waiting` (2026-09-06) is the session's own
   turn being over while work it started is not: a backgrounded subagent, or a
   command left running. Its own state because `idle` and it differ in *kind* —
   `idle` means the session is waiting for a person, and this means it is