Consolidates the personal dsh-tui customizations (module split into
components/session/extension, prompt template + running-glyph indicator,
copyable transcript, tool-card headers, timing placement, XML tool output,
status/footer rework) and ports upstream's model reasoning-effort selector
(Shift+Tab effort cycling, effort-aware /model, footer, and /status) onto
the personal module layout.
Replace send/steer/inject with one Agent.send primitive over the
(target × wakeup) matrix; followup/steer/inject become fixed-preset
alias methods on the now-abstract Agent class. Coalesce context/message
into user/message (injected context is a non-user source). Replace
agent/queued with agent/inbox/enqueue/dequeue/discard, add cancel
keepInbox, and add a FIFO-conservation invariant.