refactor: make actor graph builder fragment aware

[wenym1]

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What's changed and what's your intention?

Previously, when we handle ddls that mutate the streaming graph, we store the all dispatcher and merge update in a single vec or map. In this PR, we change to store and pass these information in per-fragment granularity, so that we can get finer-grained information when we handle these updates.

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• My PR contains critical fixes that are necessary to be merged into the latest release.

Documentation

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Release note

[wenym1]

• refactor(meta): deprecate persisted actor upstreams and get upstreams from dispatcher info #20387
• feat(meta): let stream actors in fragment share same stream node #20310
• refactor: make actor graph builder fragment aware #20385 👈 (View in Graphite)
• refactor(meta): do not store upstream actors in merge node #20222
• main

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