Respect disabled OpenCode variants and refresh WSL settings safely (#23328)

Respect disabled OpenCode variants, preserve explicit config ownership, and refresh WSL guest settings safely across reconnects.

Based on Harshul Rathod proposal #22805.

Co-authored-by: Harshul Rathod <harshulrathod1640@gmail.com>

src/shared/opencode-launch-command.ts

@@ -1,8 +1,31 @@
 import { getCommandTokenPathBasename, getFirstCommandToken } from './command-token-scanner'
+import type { TuiAgent } from './tui-agent'
 
-export function isOpenCode2LaunchCommand(launchCommand: string | undefined): boolean {
+function openCodeCommandAgent(launchCommand: string | undefined): 'opencode' | 'opencode2' | null {
   const binary = getCommandTokenPathBasename(getFirstCommandToken(launchCommand ?? ''))
     .toLowerCase()
     .replace(/\.(?:cmd|exe|sh)$/, '')
-  return binary === 'opencode2'
+  return binary === 'opencode' || binary === 'opencode2' ? binary : null
+}
+
+export function isOpenCode2LaunchCommand(launchCommand: string | undefined): boolean {
+  return openCodeCommandAgent(launchCommand) === 'opencode2'
+}
+
+export function selectOpenCodeHookAgent(
+  launchAgent: TuiAgent | undefined,
+  launchCommand: string | undefined,
+  isEnabled: (agent: 'opencode' | 'opencode2') => boolean
+): 'opencode' | 'opencode2' | null {
+  const explicit =
+    launchAgent === 'opencode' || launchAgent === 'opencode2'
+      ? launchAgent
+      : launchAgent === undefined
+        ? openCodeCommandAgent(launchCommand)
+        : null
+  // An explicit version selects its own integration; disabling it never substitutes the other.
+  if (explicit) {
+    return isEnabled(explicit) ? explicit : null
+  }
+  return isEnabled('opencode') ? 'opencode' : isEnabled('opencode2') ? 'opencode2' : null
 }