Fix a few bugs.

- Moving lines after themselves didnt work.
- moving empty lines deleted them.
- "w" didnt set state to unmodified in generic buffers.
- in "hl" aligned the numbers (by digits)

src/internal/functions/posix.cc

@@ -416,8 +416,7 @@ void Function::register_posix(BEd &ctx) {
         auto addr = std::get<buffer::Range>(addr_);
         auto arg = std::get<buffer::Line>(arg_);
         if (arg.buffername == addr.buffername
-            && addr.start <= arg.number
-            && addr.end < arg.number)
+            && arg.number >= addr.start && arg.number < addr.end)
           throw ed_error("Can't move lines within themselves.");
         auto text = ctx.buffer(addr.buffername).copy(addr.start, addr.end);
         ctx.mark(252, arg);
@@ -757,6 +756,7 @@ void Function::register_posix(BEd &ctx) {
           vase::Shard::release(text);
           throw;
         }
+        buf.saved_hook();
         if (!ctx.suppress_mode)
           ctx.io.write(std::format("{}\n", text ? text->length + 1 : 0));
       }