Add subscription network type filtering

[eliotcougar]

Summary

• add an optional network type filter directly after the subscription remarks filter
• accept case-insensitive, comma-separated transport values such as ws, grpc, and xhttp
• persist the filter with the subscription and apply it while parsing imported profiles
• localize the field label and placeholder across all nine maintained catalogs

Why

Subscription groups can currently filter imported profiles by remarks, but not by transport type. Users therefore cannot retain only profiles using selected transports without encoding that information into profile remarks.

Closes #6040.

User impact

Leaving the new field blank preserves the existing import behavior. When values are supplied, only profiles whose network type matches one of the comma-separated entries are imported. Matching ignores case and surrounding whitespace.

Validation

• :app:compilePlaystoreDebugKotlin
• XML structural audit: all nine catalogs contain 452 ordered resource identifiers with no duplicates
• git diff --check

No test source files are included in this PR.