Replace session picker modal with instance welcome view

Transform the session picker from a modal into a comprehensive welcome screen that displays instance metadata, session history, and creation options. The new view provides full keyboard navigation, shows MCP server status, OpenCode binary path, and project information in a compact, space-efficient layout.

Key features:
- Instance metadata sidebar showing folder, project, VCS, version, binary path, MCP status, and server info
- Session list with keyboard navigation (↑↓, PgUp/PgDn, Home/End, Enter)
- Cmd+Enter shortcut to create new session from anywhere
- Compact design with efficient space usage
- Visual MCP server status indicators (running/stopped/error)
- Scrollable layout that keeps "New Session" section accessible

src/stores/instances.ts

@@ -3,7 +3,6 @@ import type { Instance, LogEntry } from "../types/instance"
 import { sdkManager } from "../lib/sdk-manager"
 import { sseManager } from "../lib/sse-manager"
 import { fetchSessions, fetchAgents, fetchProviders } from "./sessions"
-import { showSessionPicker } from "./ui"
 
 const [instances, setInstances] = createSignal<Map<string, Instance>>(new Map())
 const [activeInstanceId, setActiveInstanceId] = createSignal<string | null>(null)
@@ -57,7 +56,7 @@ async function createInstance(folder: string): Promise<string> {
   addInstance(instance)
 
   try {
-    const { id: returnedId, port, pid } = await window.electronAPI.createInstance(id, folder)
+    const { id: returnedId, port, pid, binaryPath } = await window.electronAPI.createInstance(id, folder)
 
     const client = sdkManager.createClient(port)
 
@@ -66,6 +65,7 @@ async function createInstance(folder: string): Promise<string> {
       pid,
       client,
       status: "ready",
+      binaryPath,
     })
 
     setActiveInstanceId(id)
@@ -79,8 +79,6 @@ async function createInstance(folder: string): Promise<string> {
       console.error("Failed to fetch initial data:", error)
     }
 
-    showSessionPicker(id)
-
     return id
   } catch (error) {
     updateInstance(id, {

src/stores/ui.ts

@@ -3,19 +3,10 @@ import { createSignal } from "solid-js"
 const [hasInstances, setHasInstances] = createSignal(false)
 const [selectedFolder, setSelectedFolder] = createSignal<string | null>(null)
 const [isSelectingFolder, setIsSelectingFolder] = createSignal(false)
-const [sessionPickerInstance, setSessionPickerInstance] = createSignal<string | null>(null)
 
 const [instanceTabOrder, setInstanceTabOrder] = createSignal<string[]>([])
 const [sessionTabOrder, setSessionTabOrder] = createSignal<Map<string, string[]>>(new Map())
 
-function showSessionPicker(instanceId: string) {
-  setSessionPickerInstance(instanceId)
-}
-
-function hideSessionPicker() {
-  setSessionPickerInstance(null)
-}
-
 function reorderInstanceTabs(newOrder: string[]) {
   setInstanceTabOrder(newOrder)
 }
@@ -35,9 +26,6 @@ export {
   setSelectedFolder,
   isSelectingFolder,
   setIsSelectingFolder,
-  sessionPickerInstance,
-  showSessionPicker,
-  hideSessionPicker,
   instanceTabOrder,
   setInstanceTabOrder,
   sessionTabOrder,