The provider-agnostic half of PR #105863, so a CLI-driven subscription provider can ship as a
standalone `kind: model-provider` plugin instead of a bundled one:
- ProviderProfile: `native_reasoning_details_type`, `model_aliases`, `get_model_context_length`,
`get_usage_cost`, `setup_status`, `discover_models` hooks (all default None / no-op).
- Chat Completions transport: provider-native `reasoning_details` carriers follow only their
declaring profile; standard records still replay on OpenRouter-style routes, strict routes
drop the field wholesale (#70233). Relay/stream accumulate `delta.reasoning_details` verbatim.
- `hermes model`: the generic plugin flow gates an external-process row on the CLI's own login
status (inline `login_command` on a TTY), offers `discover_models()` rows with per-row notes,
and never writes config when the executable is missing.
- `/model` and the pickers: process providers list their live catalog merged with the pinned
one, declared aliases/ids resolve inside the provider, and validation accepts a listed id
without probing `process://`.
- Delegation keeps the selected external-process provider and protocol for the child.
- Model metadata / usage pricing consult the profile's bound and cost hooks first.
- Desktop: `[1m]` renders as a "1M" tag and hyphenated Anthropic versions read "Haiku 4.5".
The bespoke `_model_flow_external_process` and hard-coded `hermes_cli/main.py` paths from the
PR were dropped in favour of main's `_model_flow_plugin_provider`.
Co-authored-by: unsupportedpastels <unsupportedpastels@users.noreply.github.com>