fix(desktop): honor pre-session model pick + restore global reasoning/speed defaults (#47447)

* fix(desktop): keep the pre-session model pick selected in the picker

The composer picker derived its "current" row from `model.options ?? store`,
so model.options always won. Pre-session that query returns the PROFILE
DEFAULT, not the sticky composer pick — so selecting a model before a session
exists left the checkmark (and the picker's "current" line) on the default,
making the pick look ignored even though the pill updated.

Add `currentPickerSelection()`: with a live session the gateway's model.options
is authoritative; pre-session the sticky `$currentModel`/`$currentProvider`
wins, falling back to options. Wire it into ModelMenuPanel and ModelPickerDialog.

* feat(desktop): global reasoning/speed defaults in Settings → Model

The composer picker is now sticky-UI/per-session only and never writes the
profile default (#46959), but Settings → Model had no reasoning/speed control
and `agent.reasoning_effort` wasn't in the curated config surface at all
(`service_tier` was buried in Advanced) — so there was nowhere to set the
profile default that crons/subagents/messaging resolve from.

Add capability-gated Reasoning (effort) + Fast controls beside the main model,
gated by the applied model's reported capabilities (reasoning defaults on, fast
off when unreported — same as the composer). They read/write `agent.reasoning_effort`
and `agent.service_tier` by round-tripping the config record, matching the
gateway's value semantics (service_tier "fast"/"priority"/"on" ⇒ fast).

* refactor(desktop): don't open the reasoning select from its row label

A <label> wrapping the Select forwarded text clicks to the trigger, opening
the dropdown unexpectedly. Plain row for reasoning; Fast stays a <label> so
clicking its text toggles the switch (expected for a checkbox-like control).

apps/desktop/src/components/model-picker.tsx

@@ -2,6 +2,7 @@ import { useQuery } from '@tanstack/react-query'
 import { useState } from 'react'
 
 import { useI18n } from '@/i18n'
+import { currentPickerSelection } from '@/lib/model-status-label'
 import type { ModelOptionProvider, ModelOptionsResponse, ModelPricing } from '@/types/hermes'
 
 import type { HermesGateway } from '../hermes'
@@ -66,8 +67,13 @@ export function ModelPickerDialog({
   })
 
   const providers = modelOptions.data?.providers ?? []
-  const optionsModel = String(modelOptions.data?.model ?? currentModel ?? '')
-  const optionsProvider = String(modelOptions.data?.provider ?? currentProvider ?? '')
+
+  const { model: optionsModel, provider: optionsProvider } = currentPickerSelection(
+    !!sessionId,
+    { model: currentModel, provider: currentProvider },
+    modelOptions.data
+  )
+
   const loading = modelOptions.isPending && !modelOptions.data
 
   const error = modelOptions.error