Add InfluxQL reference content for InfluxDB 3 Cloud

Nobody has claimed this yet.

Cloud pages don't exist yet at the paths below, so [`content/influxdb3/cloud/request-information.md`](https://github.com/influxdata/docs-v2/blob/master/content/influxdb3/cloud/request-information.md) aliases them to a "Request more information" page. Publish the real content and remove the alias.

Closest existing equivalent to source from: `/influxdb3/enterprise/reference/influxql/`

## Aliased paths

- [ ] `/influxdb3/cloud/reference/influxql/`
- [ ] `/influxdb3/cloud/reference/influxql/feature-support/`
- [ ] `/influxdb3/cloud/reference/influxql/functions/`
- [ ] `/influxdb3/cloud/reference/influxql/functions/aggregates/`
- [ ] `/influxdb3/cloud/reference/influxql/functions/date-time/`
- [ ] `/influxdb3/cloud/reference/influxql/functions/selectors/`
- [ ] `/influxdb3/cloud/reference/influxql/group-by/`
- [ ] `/influxdb3/cloud/reference/influxql/regular-expressions/`
- [ ] `/influxdb3/cloud/reference/influxql/select/`
- [ ] `/influxdb3/cloud/reference/influxql/show/`
- [ ] `/influxdb3/cloud/reference/influxql/time-and-timezone/`
- [ ] `/influxdb3/cloud/reference/influxql/where/`

## Anchors the new content must provide

Shared content deep-links to these fragments. They're currently faked as hidden ``s in `request-information.md`; remove each span once the real heading exists.

- `#default-time-range`
- `#from-clause`
- `#identifiers`
- `#keywords`
- `#logical-operators`
- `#measurement_expression`
- `#notable-select-statement-behaviors`
- `#show-field-keys`
- `#show-field-values`
- `#show-measurements`
- `#time`
- `#time-ranges`
- `#time-syntax`

## Done when

- [ ] Content is published (or the linking shared content is gated for Cloud)
- [ ] The alias is removed from `request-information.md`
- [ ] Any hidden anchor ``s that belonged to these paths are removed
- [ ] `link-checker` passes

Part of #7391.

Start with the existing content under /influxdb3/enterprise/reference/influxql/ and compare it with the aliased paths in content/influxdb3/cloud/request-information.md. Publish the corresponding Cloud reference pages, remove the alias and hidden anchor spans, and verify that the shared-content links resolve and link-checker passes.

Written by the indexing model from the issue text.