v0.10.1 — a real first run + clean piped output

Two terminal-UX fixes, both found by dogfooding a fresh pip install blueshark-forge.

First-run experience (#36)
Bare forge on a fresh install used to spin a "loading model…" spinner for a
few seconds and then drop into a chat pointed at a placeholder default model the
user had never installed — no guidance, no sign of what the machine could run.
Now it shows the machine's hardware, the model-size ceiling it can run, and the
two commands to get going (forge models, forge models use phi-2, forge run),
with forge setup as the manual path. forge run "…" exits 1 with the same
pointer instead of the same dead end. Once a model is configured, nothing changes.

Clean piped output (#37)
The thinking/loading spinner and the forge models --all scan progress wrote
\r, ANSI color, and \033[K unconditionally — leaking escape-code spam into
forge run … > log, | tee, and CI capture. Both now animate only on a real
terminal (sys.stdout.isatty()); off-TTY they're silent and the results print
clean.

No API changes. 716 tests.