Restructure repo (#251)

* refactor: restructure src/ into modules/, scripts/, and build/

- src/nag_screen/ and src/node_info/ -> src/modules/  (mods grouped explicitly)
- src/Scripts/ -> src/scripts/                        (lowercase, consistent)
- src/gen-rules.sh -> build/                          (build tool separated from source)

Update all references: debian/rules, .github/workflows/*, build/gen-rules.sh,
src/scripts/test/test-syntax.sh (SRC_DIR now points to src/modules/),
src/scripts/test/test-patches.sh, and files.list comments.

* refactor: move CI test scripts from src/scripts/test/ to build/test/

Test scripts are not installed — they are CI/dev tooling and belong
alongside build/gen-rules.sh. Update workflow references and fix the
SRC_DIR path depth in build/test/test-syntax.sh (../ -> ../..).

* d

---------

Co-authored-by: Meliox <na>

debian/rules

@@ -6,18 +6,18 @@ override_dh_install:
 	# ── Static section ─────────────────────────────────────────────────────
 	# Generic, mod-independent files that never change when mods are added.
 	# Everything mod-specific (module files, patches, per-mod configs) is
-	# generated and appended below by src/gen-rules.sh at build time and is
+	# generated and appended below by build/gen-rules.sh at build time and is
 	# NOT committed to the repository.
 	#
 	# Patch helpers (generic, manifest-driven)
-	install -Dm755 src/Scripts/apply-patches.sh debian/pve-mod/usr/lib/pve-mod/apply-patches.sh
-	install -Dm755 src/Scripts/revert-patches.sh debian/pve-mod/usr/lib/pve-mod/revert-patches.sh
+	install -Dm755 src/scripts/apply-patches.sh debian/pve-mod/usr/lib/pve-mod/apply-patches.sh
+	install -Dm755 src/scripts/revert-patches.sh debian/pve-mod/usr/lib/pve-mod/revert-patches.sh
 	# Configure tool
-	install -Dm755 src/Scripts/pve-mod-configure debian/pve-mod/usr/sbin/pve-mod-configure
+	install -Dm755 src/scripts/pve-mod-configure debian/pve-mod/usr/sbin/pve-mod-configure
 	# Main config (conffile for user edits)
 	install -Dm644 src/pve-mod.conf debian/pve-mod/etc/pve-mod/pve-mod.conf
 	# Main config reference copy for upgrade key-diff (not a conffile)
 	install -Dm644 src/pve-mod.conf debian/pve-mod/usr/share/pve-mod/pve-mod.conf.default
 	# ── Dynamic section ────────────────────────────────────────────────────
-	# `bash src/gen-rules.sh >> debian/rules` appends per-module install lines
+	# `bash build/gen-rules.sh >> debian/rules` appends per-module install lines
 	# here during CI, just before dpkg-buildpackage. Do not commit them.