Broadcastify allow/deny talkgroup filters (glob patterns)

[TheGreatCodeholio]

This PR modernizes and extends Broadcastify talkgroup filtering by introducing
allow/deny terminology and glob-style pattern matching, while preserving
backward compatibility with existing configs.

What changed

• Added per-system talkgroup filters:
  • broadcastifyAllow: if non-empty, the talkgroup MUST match at least one
    pattern or the upload is skipped
  • broadcastifyDeny: if non-empty, any matching talkgroup is skipped
• Patterns are glob-style (compiled to anchored regex):
  • • matches any length
  • ? matches exactly one character
• Filter order:
  1. allow check (if present)
  2. deny check (if present)

Docs / examples

• Updated config docs to describe broadcastifyAllow / broadcastifyDeny as arrays
  of string/number.
• Added examples showing both * and ? usage (e.g., "507*" and "12?45").

Notes

• Filtering compares against the numeric talkgroup ID coerced to a string
  (e.g., 50712) so behavior is consistent whether config entries are strings
  or numbers.
• When a call is skipped due to filters, we log an info message including the
  talkgroup ID for easier debugging.

Requesting review on naming consistency and the compatibility-key priority
ordering, but functionally this is a safe, additive upgrade.

54% less racist then before.

[robotastic]

This looks straightforward to me and a good idea. I don't have Broadcastify uploading set up on my machine. Can someone give this code a run and see if it also works for them?