tui: add session rename functionality with /rename command

- Add /rename command to autocomplete when a session is active
- Add rename dialog component for changing session names
- Add rename option to session list dialog with 'r' keybind
- Add session rename command to command registry

packages/opencode/src/cli/cmd/tui/ui/dialog-prompt.tsx

@@ -0,0 +1,65 @@
+import { TextareaRenderable, TextAttributes } from "@opentui/core"
+import { useTheme } from "../context/theme"
+import { useDialog, type DialogContext } from "./dialog"
+import { onMount } from "solid-js"
+
+export type DialogPromptProps = {
+  title: string
+  value?: string
+  onConfirm?: (value: string) => void
+  onCancel?: () => void
+}
+
+export function DialogPrompt(props: DialogPromptProps) {
+  const dialog = useDialog()
+  const { theme } = useTheme()
+  let textarea: TextareaRenderable
+
+  onMount(() => {
+    dialog.setSize("large")
+    setTimeout(() => {
+      textarea.focus()
+    }, 1)
+    textarea.gotoLineEnd()
+  })
+
+  return (
+    <box paddingLeft={2} paddingRight={2} gap={1}>
+      <box flexDirection="row" justifyContent="space-between">
+        <text attributes={TextAttributes.BOLD}>{props.title}</text>
+        <text fg={theme.textMuted}>esc</text>
+      </box>
+      <box>
+        <textarea
+          onSubmit={() => {
+            props.onConfirm?.(textarea.plainText)
+            dialog.clear()
+          }}
+          keyBindings={[{ name: "return", action: "submit" }]}
+          ref={(val: TextareaRenderable) => (textarea = val)}
+          initialValue={props.value}
+          placeholder="Enter text"
+        />
+      </box>
+      <box paddingBottom={1}>
+        <text fg={theme.textMuted}>Press enter to confirm, esc to cancel</text>
+      </box>
+    </box>
+  )
+}
+
+DialogPrompt.show = (dialog: DialogContext, title: string, value?: string) => {
+  return new Promise<string | null>((resolve) => {
+    dialog.replace(
+      () => (
+        <DialogPrompt
+          title={title}
+          value={value}
+          onConfirm={(value) => resolve(value)}
+          onCancel={() => resolve(null)}
+        />
+      ),
+      () => resolve(null),
+    )
+  })
+}

packages/opencode/src/cli/cmd/tui/ui/dialog-select.tsx

@@ -138,7 +138,10 @@ export function DialogSelect<T>(props: DialogSelectProps<T>) {
     for (const item of props.keybind ?? []) {
       if (Keybind.match(item.keybind, keybind.parse(evt))) {
         const s = selected()
-        if (s) item.onTrigger(s)
+        if (s) {
+          evt.preventDefault()
+          item.onTrigger(s)
+        }
       }
     }
   })