[mlir][Transforms] Add listener support to dialect conversion (#83425)

This commit adds listener support to the dialect conversion. Similarly
to the greedy pattern rewrite driver, an optional listener can be
specified in the configuration object.

Listeners are notified only if the dialect conversion succeeds. In case
of a failure, where some IR changes are first performed and then rolled
back, no notifications are sent.

Due to the fact that some kinds of rewrite are reflected in the IR
immediately and some in a delayed fashion, there are certain limitations
when attaching a listener; these are documented in `ConversionConfig`.
To summarize, users are always notified about all rewrites that
happened, but the notifications are sent all at once at the very end,
and not interleaved with the actual IR changes.

This change is in preparation improvements to
`transform.apply_conversion_patterns`, which currently invalidates all
handles. In the future, it can use a listener to update handles
accordingly, similar to `transform.apply_patterns`.

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