packaging: correct the debian changelog and the manpage file list

- dragonx.manpages listed DEBIAN/manpages/*.1, a path nothing creates,
  so dh_installman would fail on it. Point it at doc/man/*.1, which is
  where util/gen-manpages.sh writes and what doc/man/Makefile.am ships.
- Restore the 1.0.1 and 1.0.2 stanzas, reconstructed from the commits
  each tag actually contains. The file jumped 1.0.3 -> 1.0.0.
- The 1.1.0 and 1.0.0 trailers named weekdays that do not match their
  dates ("Thu, 21 Aug 2026" is a Friday; "Mon, 03 Mar 2026" is a
  Tuesday). Replace both with the real v1.1.0 and v1.0.0 tag dates,
  which fixes the weekday and the disagreement with the tag at once.
- Record the 1.2.0 peer-discovery work in its stanza.
- Drop doc/man/hushd.html and doc/man/hush-cli.html: stale Hush-branded
  pages for binaries this tree no longer builds, referenced by nothing.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FU87LdsJZiZkfq1eXubpeo

contrib/debian/dragonx.manpages

@@ -1,3 +1,3 @@
-DEBIAN/manpages/dragonx-cli.1
-DEBIAN/manpages/dragonx-tx.1
-DEBIAN/manpages/dragonxd.1
+doc/man/dragonxd.1
+doc/man/dragonx-cli.1
+doc/man/dragonx-tx.1