scripts / make: Add Recommends support

The spec generator only supports Requires, Conflicts and Provides from
the [pkg.requires.*], [pkg.conflicts.*] and [pkg.provides.*] sections of
make/project.conf. A package that works without but is better with another
package, like jw-amavis-run without jw-clamav-run, must hard-require it, so
the dependency is pulled in on every install and cannot be removed without
dragging the depending package along.

This commit adds Recommends support to the spec generation chain:

- CmdPkgRecommends: new pkg-recommends command that reads the
  [pkg.recommends.<flavour>] sections, same base as pkg-requires
- pkg-dist.mk: compute PKG_RECOMMENDS_RUN and pass it to pkg.sh via a new
  -E option
- pkg.sh: accept -E and forward it to the mkspec wrapper
- mkspec-wrapper.sh: accept -E and export RECOMMENDS_RUN
- create-mkspec.sh: emit a Recommends: line when RECOMMENDS_<subpkg> is set
- create-mkdebian.sh: emit a Recommends: field in the debian control file

Projects without a [pkg.recommends.*] section generate unchanged specs:
every new line is guarded by a non-empty test. zypper follows Recommends by
default, so existing OpenSUSE installations are unaffected; a recommended
package can be removed without dragging the depending package along.

Assisted-by: unsloth/Qwen3.8-27B-GGUF:Q4_K_M with pi.dev v0.85.1
Signed-off-by: Jan Lindemann <jan@janware.com>

scripts/create-mkspec.sh

@@ -112,6 +112,7 @@ for p in $subpackages; do
 		|echo "Summary: `cfg_value summary`"
 		|echo "Group: `cfg_value global.group`"
 		|[ "\$REQUIRES_$P" ] && echo "Requires: \$REQUIRES_$P"
+		|[ "\$RECOMMENDS_$P" ] && echo "Recommends: \$RECOMMENDS_$P"
 		|[ "\$CONFLICTS_$P" ] && echo "Conflicts: \$CONFLICTS_$P"
 		|[ "\$PROVIDES_$P" ] && echo "Provides: \$PROVIDES_$P"
 		|echo ""