0.0.154

Default model setting replaces the Auto pseudo-model

Settings gains a Default Model (core.settings/app `default_model`,
GET/PUT /api/settings/default-model). Dispatch resolves an unset or
legacy auto/default model to it, keeping effort-based routing only as
the fallback when nothing is configured.

ModelPicker no longer injects an Auto row: the empty option renders
only where a defaultLabel is passed. New sessions, cards, reviews and
repeating tasks preselect the configured default; the session toolbar
shows the default's name for unpinned sessions; project modals keep an
explicit "App default" inherit option.

Covered by dispatch_resolves_unset_model_to_default_model_setting plus
updated model-picker-search / overlay-primitives / doc-review e2e (model
option testids are provider-prefixed, e.g. claude:claude-opus-4-8).

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