fix: handle symlinks when scanning user/project skill directories

Previously collectSkillsFromRoots only checked isDirectory(), which
returns false for symbolic links on some platforms (particularly
Windows). This caused symlinked skills in ~/.claude/skills/ to be
silently skipped in the settings UI. The plugin scanning path already
had the correct isDirectory() || isSymbolicLink() guard — this aligns
the user/project scanning to match.

Author: tangdogdaihuman

src/server/api/skills.ts

@@ -224,7 +224,7 @@ async function collectSkillsFromRoots(
     }
 
     for (const entry of entries) {
-      if (!entry.isDirectory() || entry.name.startsWith('.') || seenNames.has(entry.name)) {
+      if ((!entry.isDirectory() && !entry.isSymbolicLink()) || entry.name.startsWith('.') || seenNames.has(entry.name)) {
         continue
       }