fix(buddy): address CodeRabbit review findings

- buddy.ts: return type Promise<null> → Promise<React.ReactNode>
  to match LocalJSXCommandCall interface (CompanionCard path returns
  ReactElement, not null).
- CompanionCard.tsx: clamp stat value to 0..100 before .repeat()
  to prevent negative count runtime error on out-of-range values.

Import path alias suggestions (src/ vs ../) dismissed — project
convention uses relative paths (verified against color.ts, help.ts).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/buddy/CompanionCard.tsx

@@ -12,7 +12,8 @@ const CARD_WIDTH = 40;
 const CARD_PADDING_X = 2;
 
 function StatBar({ name, value }: { name: string; value: number }) {
-  const filled = Math.round(value / 10);
+  const clamped = Math.max(0, Math.min(100, value));
+  const filled = Math.round(clamped / 10);
   const bar = '\u2588'.repeat(filled) + '\u2591'.repeat(10 - filled);
   return (
     <Text>

src/commands/buddy/buddy.ts

@@ -71,7 +71,7 @@ export async function call(
   onDone: LocalJSXCommandOnDone,
   context: ToolUseContext & LocalJSXCommandContext,
   args: string,
-): Promise<null> {
+): Promise<React.ReactNode> {
   const sub = args?.trim().toLowerCase() ?? ''
   const setState = context.setAppState