fix: use realpathSync.native for session projectId hash on Windows (#1593) (#1601)

On Windows, path.resolve returns whatever case the caller supplied while
fs.realpathSync.native returns the OS-canonical case. These produce
different SHA-1 hashes and therefore different session tmpdir slots —
the test checks one slot while the implementation writes to another,
causing pointer lifecycle assertions to always fail.

Fix: use realpathSync.native with a fallback to path.resolve when the
planning directory does not yet exist.

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

get-shit-done/bin/lib/core.cjs

@@ -695,9 +695,20 @@ function getSessionScopedWorkstreamFile(cwd) {
   const sessionKey = getWorkstreamSessionKey();
   if (!sessionKey) return null;
 
+  // Use realpathSync.native so the hash is derived from the canonical filesystem
+  // path. On Windows, path.resolve returns whatever case the caller supplied,
+  // while realpathSync.native returns the case the OS recorded — they differ on
+  // case-insensitive NTFS, producing different hashes and different tmpdir slots.
+  // Fall back to path.resolve when the directory does not yet exist.
+  let planningAbs;
+  try {
+    planningAbs = fs.realpathSync.native(planningRoot(cwd));
+  } catch {
+    planningAbs = path.resolve(planningRoot(cwd));
+  }
   const projectId = crypto
     .createHash('sha1')
-    .update(path.resolve(planningRoot(cwd)))
+    .update(planningAbs)
     .digest('hex')
     .slice(0, 16);