refactor(source): rename some source parser related types and methods

[stdrc]

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What's changed and what's your intention?

To make code more understandable.

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

• My PR needs documentation updates.

Release note

[stdrc]

• refactor(source): rename some source parser related types and methods #19863 👈 (View in Graphite)
• refactor(source): respect max chunk size in source connector parser #19698 : 1 other dependent PR (#19826 )
• refactor(cdc source): merge cdc heartbeat chunk builder & data chunk builder #19671
• refactor(connector): re-arrange the connector::parser module for better readibility #19697
• main

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