fix(glob): throw descriptive error for unbalanced braces in glob patterns

[Thavamani13]

Summary

• globToRegexPattern() unconditionally emitted ( / ) for { / } with no balance check, producing invalid regex (e.g. /^(foo$/) that threw SyntaxError at request-match time and silently aborted navigation
• Added guards to throw a clear Invalid glob pattern error at parse time for unmatched {, unmatched }, and nested {
• Added 6 test assertions covering the reported patterns

Fixes #40422