curl examples, misc syntax

> @copilot file your unresolved comments in a single separate issue

I don’t have issue-creation permissions with the tools available in this environment. Please file one issue with these unresolved review items:
- `content/shared/influxdb3-get-started/query.md:323-324`: split `curl` command missing line-continuation `\`.
- `content/shared/influxdb3-sample-data/sample-data.md:97` (and similar URLs in file): `curl` URL with `&` query params should be quoted.
- `content/shared/influxdb3-sample-data/sample-data-dist.md:100`: `curl` URL with `&` query params should be quoted.

_Originally posted by @copilot-swe-agent in https://github.com/influxdata/docs-v2/pull/7503#issuecomment-4991393914_

Start with the curl examples at content/shared/influxdb3-get-started/query.md:323-324 and the related examples in content/shared/influxdb3-sample-data/sample-data.md and sample-data-dist.md. Check the listed commands for the missing line continuation and unquoted URLs containing query parameters. Done means all identified examples use valid shell syntax consistently.

Written by the indexing model from the issue text.