fix: escape attribute and matching rule in DecompileFilter

[netliomax25-code]

1. DecompileFilter runs the assertion value through EscapeFilter, but the attribute description (equality, substrings, >=, <=, ~=, present) and the extensible-match attribute and matching rule are written to the output verbatim.
2. A filter packet from an untrusted peer whose attribute or matching-rule bytes contain the filter metacharacters ()*\ breaks out of its component and injects extra clauses into the reconstructed string. An equality packet with attribute uid)(uid=admin decompiles to (uid)(uid=admin=x).

Ran each attribute emission and the extensible-match matching rule through EscapeFilter, the same way the value is already handled. Legitimate attribute descriptors are ASCII and contain none of the escaped characters, so existing round-trips are unchanged. Added a regression test that builds the crafted packets and checks the metacharacters come back escaped.