feat(worker): add hg-edge and bugzilla pollers

Wires two historical sources for completeness with the 2019 timeline:

- hg-edge.mozilla.org: scans json-pushes for a configured set of
  build/* repos and matches changeset author client-side, since the
  pushlog `user=` filter targets the pusher (sheriffs/reviewers in
  this case) rather than the author. Daily poll cadence — mozilla
  retired hg, no new events expected.
- bugzilla.mozilla.org: queries /rest/bug?creator=<email>. Without
  an api key the unauthenticated endpoint only returns public bugs,
  which is what the public timeline wants anyway.

Reshape renders "<author> committed <short_node> in <repo>" for hg
and "filed bug #<id> in <product>" for bugzilla, both linking back
to the canonical upstream URL via a stamped `_host` payload field.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/moments-data/src/lib.rs

@@ -1,6 +1,8 @@
+pub mod bugzilla;
 pub mod gitea;
 pub mod github;
 pub mod github_search;
+pub mod hg;
 
 use async_trait::async_trait;
 use chrono::{DateTime, Utc};