chore: snapshot working tree - pty_exited notifications + in-flight inference WIP

feat(booterm): structured pty_exited WS notifications. Plan-validated, impl-validated, code-reviewed green (contracts build clean, contracts test 29/29, booterm + web typecheck clean).

wip: in-progress inference/provider refactor (agents.ts, provider.ts, new llama-providers.ts, removed llama-args-validator), plus arena, dispatcher, compaction, schema changes.

openspec: pty-exit-notifications complete; x-agent-flags planned (not yet implemented).

apps/web/src/components/AgentComposerBar.tsx

@@ -1,5 +1,5 @@
 import { useEffect, useMemo, useRef, useState } from 'react';
-import { Check, ChevronDown, RefreshCw, Loader2, Shield, ShieldAlert, Eye, Brain, Bot } from 'lucide-react';
+import { Check, ChevronDown, RefreshCw, Loader2, Shield, ShieldAlert, Eye, Brain, Bot, Star } from 'lucide-react';
 import { api } from '@/api/client';
 import type { AgentSessionConfig, ProviderSnapshotEntry, AgentCommand } from '@/api/types';
 import { useProviderSnapshot, refreshProviderSnapshot } from '@/hooks/useProviderSnapshot';
@@ -9,6 +9,8 @@ import {
   DropdownMenu,
   DropdownMenuContent,
   DropdownMenuItem,
+  DropdownMenuLabel,
+  DropdownMenuSeparator,
   DropdownMenuTrigger,
 } from '@/components/ui/dropdown-menu';
 import { BottomSheet } from '@/components/BottomSheet';
@@ -113,14 +115,22 @@ interface PickerProps {
   /** Grow to fill the row's free space and render the value brighter — used for
    *  the Model picker so the active model is the most visible control. */
   flexible?: boolean;
+  /** Grouped rendering: renders sections with labels (Favorites-first, then
+   *  per-provider). When provided, `options` is ignored. */
+  groups?: ModelGroup[];
 }
 
-function CompactPicker({ label, value, disabled, options, onPick, icon, iconOnly, flexible }: PickerProps) {
+interface ModelGroup {
+  label: string;
+  options: Array<{ id: string; label: string }>;
+}
+
+function CompactPicker({ label, value, disabled, options, onPick, icon, iconOnly, flexible, groups }: PickerProps) {
   const { isMobile } = useViewport();
   const [open, setOpen] = useState(false);
   const currentLabel = options.find((o) => o.id === value)?.label ?? (value || label);
 
-  const list = (
+  const flatList = (
     <div className="py-1">
       {options.map((o) => (
         <button
@@ -139,6 +149,36 @@ function CompactPicker({ label, value, disabled, options, onPick, icon, iconOnly
     </div>
   );
 
+  const groupedList = (
+    <div className="py-1">
+      {groups!.map((g, gi) => {
+        if (g.options.length === 0) return null;
+        return (
+          <div key={g.label}>
+            {gi > 0 && <div className="h-px bg-border mx-2 my-1" />}
+            <div className="text-[10px] font-medium text-muted-foreground px-2 py-0.5 uppercase tracking-wider">{g.label}</div>
+            {g.options.map((o) => (
+              <button
+                key={o.id}
+                type="button"
+                onClick={() => {
+                  onPick(o.id);
+                  setOpen(false);
+                }}
+                className="w-full text-left flex items-center gap-2 font-mono text-xs px-2 py-1.5 hover:bg-accent rounded"
+              >
+                <Check className={cn('size-3 shrink-0', o.id === value ? 'opacity-100' : 'opacity-0')} />
+                <span className="truncate">{o.label}</span>
+              </button>
+            ))}
+          </div>
+        );
+      })}
+    </div>
+  );
+
+  const list = groups ? groupedList : flatList;
+
   if (isMobile) {
     return (
       <>
@@ -243,6 +283,8 @@ function AgentStatusDot({ entry, agent }: { entry: AgentStatusEntry; agent: stri
   );
 }
 
+const FAVORITE_MODELS_KEY = 'favorite_models';
+
 export function AgentComposerBar({ projectPath, value, onChange, onProviderCommandsChange, connected, agentStatus }: Props) {
   const allEntries = useProviderSnapshot(projectPath);
   // 5.5 — the composer picker only offers ENABLED providers that are ready (or
@@ -254,9 +296,20 @@ export function AgentComposerBar({ projectPath, value, onChange, onProviderComma
     [allEntries],
   );
   const [refreshing, setRefreshing] = useState(false);
+  const [favoriteModels, setFavoriteModels] = useState<string[]>([]);
 
   const hydratedRef = useRef(false);
 
+  // Fetch favorites from settings for the grouped model picker (W5).
+  useEffect(() => {
+    api.settings.get().then((settings) => {
+      const raw = settings[FAVORITE_MODELS_KEY];
+      if (Array.isArray(raw)) {
+        setFavoriteModels(raw.filter((m): m is string => typeof m === 'string'));
+      }
+    }).catch(() => { /* settings fetch is best-effort */ });
+  }, []);
+
   useEffect(() => {
     hydratedRef.current = false;
   }, [projectPath]);
@@ -318,6 +371,54 @@ export function AgentComposerBar({ projectPath, value, onChange, onProviderComma
     onProviderCommandsChange?.(currentEntry?.commands ?? []);
   }, [currentEntry, onProviderCommandsChange]);
 
+  // Build grouped model options for the native boocode provider (W5).
+  // For other providers, use a flat list. Groups: Favorites first, then
+  // one section per local provider prefix (matching BooChat's ModelPicker).
+  const modelGroups = useMemo<ModelGroup[] | null>(() => {
+    if (!currentEntry || currentEntry.name !== 'boocode') return null;
+    const models = currentEntry.models;
+    if (models.length === 0) return [];
+
+    const favSet = new Set(favoriteModels);
+
+    // Build a model map for quick lookup
+    const modelMap = new Map(models.map((m) => [m.id, m]));
+
+    // Group models by provider prefix (the part before the first slash)
+    const byProvider = new Map<string, Array<{ id: string; label: string }>>();
+    for (const m of models) {
+      const slash = m.id.indexOf('/');
+      const providerPrefix = slash > 0 ? m.id.slice(0, slash) : 'other';
+      const formatted = { id: m.id, label: formatModelLabel(m.label) };
+      const arr = byProvider.get(providerPrefix) ?? [];
+      arr.push(formatted);
+      byProvider.set(providerPrefix, arr);
+    }
+
+    const groups: ModelGroup[] = [];
+
+    // Favorites section: only models that exist in the live inventory
+    const favModels = [...favSet]
+      .filter((id) => modelMap.has(id))
+      .map((id) => ({ id, label: formatModelLabel(modelMap.get(id)!.label) }));
+    if (favModels.length > 0) {
+      groups.push({ label: 'Favorites', options: favModels });
+    }
+
+    // One section per provider group
+    for (const [provider, opts] of byProvider) {
+      groups.push({ label: provider, options: opts });
+    }
+
+    return groups;
+  }, [currentEntry, favoriteModels]);
+
+  // Flat model options for non-boocode providers
+  const modelOptions = useMemo(
+    () => (currentEntry?.models ?? []).map((m) => ({ id: m.id, label: formatModelLabel(m.label) })),
+    [currentEntry],
+  );
+
   function persist(next: AgentSessionConfig): void {
     const prefs = loadPrefs();
     prefs[next.provider] = {
@@ -369,7 +470,6 @@ export function AgentComposerBar({ projectPath, value, onChange, onProviderComma
   // derived from it.
   const permissionModes = availablePermissionModes(currentEntry?.modes ?? []);
   const currentPermission = permissionForModeId(value.modeId, currentEntry?.modes ?? []);
-  const modelOptions = (currentEntry?.models ?? []).map((m) => ({ id: m.id, label: formatModelLabel(m.label) }));
   const thinkingOpts = thinkingOptions.map((t) => ({ id: t.id, label: t.label }));
 
   return (
@@ -423,8 +523,9 @@ export function AgentComposerBar({ projectPath, value, onChange, onProviderComma
       <CompactPicker
         label="Model"
         value={value.model}
-        disabled={modelOptions.length === 0}
+        disabled={modelGroups ? modelGroups.every((g) => g.options.length === 0) : modelOptions.length === 0}
         options={modelOptions}
+        groups={modelGroups ?? undefined}
         onPick={pickModel}
         icon={<Bot size={13} className="shrink-0" />}
         flexible