Fix symlink target validation and add features/license_family support to MatchSpec

[ritankarsaha]

Checklist

• I added a descriptive title
• I searched open reports and couldn't find a duplicate

What happened?

Two separate correctness gaps in the package validation and query layer:

1. Symlink target validation missing (rattler_cache): validate_package_soft_link_entry only checked
   that a path was a symlink. It never inspected the target. This means broken symlinks (dangling
   targets) and symlinks that escape the package root (via ../../ or absolute paths like /etc/passwd)
   were silently accepted as valid.

2. features and license_family not parsed in MatchSpec (rattler_conda_types): The bracket-key
   parser contained a TODO comment for these two fields. Any spec using python[license_family=MIT] or
   python[features=feature1] returned InvalidBracketKey instead of populating the field. PackageRecord
   carries both fields, but they could never be matched against.

Additional Context

No response

[baszalmstra]

Can you make two issues instead of combining them?

[ritankarsaha]

Can you make two issues instead of combining them?

Suree !! so should i break the 2 prs, close this one and make 2 issues and 2 prs?

[ritankarsaha]

@baszalmstra closing this issue now and making two separate PRs with 2 different issues here properly.