debian: lintian cleanup (metadata, compat 14, priority, NMU override)

Add debian/upstream/metadata (DEP-12), bump debhelper-compat to 14, drop the
redundant Priority: optional source field, and rename the stale NMU override
tag changelog-should-mention-nmu to no-nmu-in-changelog with a note on why the
address mismatch trips it.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Xavier Roche <roche@httrack.com>

debian/control

@@ -1,9 +1,8 @@
 Source: httrack
 Section: web
-Priority: optional
 Maintainer: Xavier Roche <roche@httrack.com>
 Standards-Version: 4.7.4
-Build-Depends: debhelper-compat (= 13), autoconf, autoconf-archive, automake, libtool, zlib1g-dev, libssl-dev
+Build-Depends: debhelper-compat (= 14), autoconf, autoconf-archive, automake, libtool, zlib1g-dev, libssl-dev
 Rules-Requires-Root: no
 Homepage: http://www.httrack.com
 Vcs-Git: https://github.com/xroche/httrack.git

debian/source/lintian-overrides

@@ -1,4 +1,6 @@
-httrack source: changelog-should-mention-nmu
+# Maintainer uploads sign the changelog as xavier@debian.org while the control
+# Maintainer is roche@httrack.com; lintian reads the address mismatch as an NMU.
+httrack source: no-nmu-in-changelog
 httrack source: source-nmu-has-incorrect-version-number
 
 # The bundled HTML pages are the genuine upstream documentation taken from

debian/upstream/metadata

@@ -0,0 +1,6 @@
+---
+Repository: https://github.com/xroche/httrack.git
+Repository-Browse: https://github.com/xroche/httrack
+Bug-Database: https://github.com/xroche/httrack/issues
+Bug-Submit: https://github.com/xroche/httrack/issues/new
+Contact: Xavier Roche <roche@httrack.com>