feat(studio): refine pipeline creation copy - #50751

Problem

The pipeline creation sheet uses generic examples, inconsistent destination terminology, and Advanced settings copy that does not explain what is being overridden. Its Docs button also sends most destinations to the general Pipelines guide.

This PR is stacked on #50719 so the shared copy builds on the focused Snowflake field improvements.

Solution

Adds destination-specific pipeline-name examples and field descriptions, clarifies destination summaries and Advanced settings, uses human-readable ClickHouse engine names, shortens the primary action to Start pipeline, and links the Docs button to the selected destination guide.

To test

• Database Replication

Review instructions

1. Open Database > Replication and click Add pipeline.
2. Switch between destination types and confirm the pipeline-name example, destination summary, and field descriptions update appropriately.
3. Open Advanced settings and confirm the batch wait-time default is shown in the description while the input placeholder is 10000.
4. Select each supported destination and confirm Docs opens its matching destination guide.
5. Select ClickHouse and confirm the engine choices read ReplacingMergeTree and MergeTree.

Checklist

• I have read CONTRIBUTING.md
• If I wrote a new docs topic or edited an existing topic, I used the /write-the-docs or /edit-the-docs skill, which references WORD_LIST and the docs CONTRIBUTING guide