* feat(native-chat): choose which agents open as a chat
Settings → Chat gets a Providers list. Each agent the host can open as a chat
has a switch; off opens that agent in a terminal instead. Only choices the user
makes are saved. Unchosen: Claude and Codex on, others on when their CLI is
installed on this computer.
The renderer's route and the host's launch-mode decision both read one rule, so
the tab menu, shortcuts, CLI, orchestration and relayed phone launches agree.
* fix: keep chat provider settings with the other chat settings types
* test: route input carries this computer's detected agents
* fix(chat): resolve provider choices from their owning computer
* test(chat): use checked native inventory fixtures
* Fix launch preparation lifetime and execution host startup
* fix(chat): keep unchosen providers on without discovery
* test(chat): type provider routing fixtures against store contracts
* test(chat): align shared launch fixture with private settings reader
* test(chat): give the structured-session RPC fixture the private settings reader
The host now reads saved chat choices through requireStore().getSettings(); the
shared RPC fixture only had getClientSettings, so the launch-mode reader saw no
settings and create support refused Claude. The fixture now follows each test's
client settings.
* fix: preserve provider choice and cached native inventory