fix: fix bugs in core modules

- tty: fix isStdoutTTY to use fstat first, fall back to TERM heuristic
- git: fix commit regex to handle root-commit output format
- git: fix parseNameStatus to handle edge cases (empty lines, missing tabs)
- ai: fix readStream to cancel reader instead of releaseLock
- cli: remove dead code resolveFlagName function
- clipboard: fix inconsistent indentation

Co-Authored-By: Claude <noreply@anthropic.com>

src/ai.ts

@@ -123,7 +123,6 @@ async function readStream(body: ReadableStream<Uint8Array>, callbacks: StreamCal
 
       buffer += decoder.decode(value, { stream: true });
       const lines = buffer.split("\n");
-      // Keep the last potentially incomplete line
       buffer = lines.pop() ?? "";
 
       for (const line of lines) {
@@ -136,7 +135,12 @@ async function readStream(body: ReadableStream<Uint8Array>, callbacks: StreamCal
         try {
           const parsed = JSON.parse(data) as {
             choices?: Array<{ delta?: { content?: string }; finish_reason?: string }>;
+            error?: { message?: string };
           };
+          if (parsed.error) {
+            callbacks.onError?.(new Error(`Stream error: ${parsed.error.message ?? "unknown"}`));
+            continue;
+          }
           const token = parsed.choices?.[0]?.delta?.content;
           if (token) {
             fullText += token;
@@ -152,7 +156,8 @@ async function readStream(body: ReadableStream<Uint8Array>, callbacks: StreamCal
       }
     }
   } finally {
-    reader.releaseLock();
+    try { await reader.cancel(); } catch {}
+    // releaseLock is not needed after cancel
   }
 
   callbacks.onDone?.(fullText);