lib.ExecContext: Support bytes-typed cmd_input

The Input instance passed as cmd_input to ExecContext.run() and
.sudo() currently may be of type str. Allow to pass bytes, too.

At the same time, disallow None to be passed as cmd_input. Force the
caller to be more explicit how it wants input to be handled, notably
with respect to interactivity.

Along the way fix a bug: Content in cmd_input should result in
CallContext.interactive == False but doesn't. Fix that.

Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/cmds/projects/CmdBuild.py

@@ -120,7 +120,6 @@ class CmdBuild(Cmd): # export
                     wd=wd,
                     throw=True,
                     verbose=True,
-                    cmd_input=None,
                     env=env,
                     title=title
                 )

src/python/jw/pkg/cmds/projects/CmdListRepos.py

@@ -43,7 +43,8 @@ class CmdListRepos(Cmd): # export
                     print('\n'.join(result.stdout.decode().splitlines()))
                     return
             case 'https':
-                cmd_input = None
+                from jw.pkg.lib.ExecContext import InputMode
+                cmd_input = InputMode.NonInteractive
                 if re.match(r'https://github.com', args.base_url):
                     curl_args = [
                         '-f',