New M-S-RET "Copy call to REPL" action for sldb and trace-dialog

* sly.el (sldb-frame-map): Set `sly-part-button-keymap' as parent
of `sly-frame-keymap'.
(sldb-frame): Make this button type inherit from `sly-part', not
`sly-button'.
(sldb-frame-button): Add `part-args' and `part-label' props to
`sldb-frame' buttons.

* contrib/sly-mrepl.el (define-sly-contrib sly-mrepl): Define a new
"part-action" `sly-mrepl-copy-call-to-repl'. Put this is
`sldb-frame' and `sly-trace-dialog-spec' button types. Rename
previous `sly-mrepl-copy-to-repl' action to
`sly-mrepl-copy-part-to-repl'
(sly-inspector-copy-part-to-repl): Renamed from
`sly-inspector-copy-down-to-repl'
(sldb-copy-part-to-repl): Renamed from `sldb-copy-down-to-repl'.
(sly-trace-dialog-copy-part-to-repl): Renamed from
`sly-trace-dialog-copy-down-to-repl'
(sly-mrepl--insert-call, sldb-copy-call-to-repl)
(sly-trace-dialog-copy-call-to-repl): New functions.

* contrib/sly-trace-dialog.el (sly-trace-dialog-spec):
`sly-button-inspect' method takes more (ignored) arguments.
(sly-trace-dialog-spec-button): `sly-trace-dialog-spec' buttons
have more props.
(sly-trace-dialog--insert-trace): Pass trace to
`sly-trace-dialog-spec-button'

* contrib/swank-trace-dialog.lisp (trace-arguments): New function.