[Feature Request] Improve DX of adding Search Attributes

[lorensr]

Is your feature request related to a problem? Please describe.

Can easily run into this error:

t operator search-attribute create --namespace default --name test4 --type Text
Error: unable to add search attributes: Unable to create search attributes: cannot have more than 3 search attribute of type Text.

Describe the solution you'd like

• Higher default max
• Say in the error how to raise the limit (or link to an error page that says it)

[chaptersix]

Did a light investigation into the current state of this.

The default limits per type for the dev server (SQLite) are still low -- 3 for most types, 10 for Keyword. These are defined in the server's common/searchattribute/sadefs/constants.go (defaultNumDBCustomSearchAttributes).

However, temporalio/temporal#8397 (Sep 2025) added server-level support for overriding these limits via a visibility.persistenceCustomSearchAttributes config. The underlying GetDBIndexSearchAttributes function now accepts an override map, and for SQLite the columns are created dynamically at startup -- so no separate schema migration would be needed for the dev server.

The gap is that the CLI dev server currently calls GetDBIndexSearchAttributes(nil), so the override is never passed through. Possible solutions:

1. Raise the defaults for the dev server (simplest -- just bump the numbers in the default map or pass higher overrides from the CLI)
2. Expose a CLI flag like --custom-search-attributes-limit that passes through to the override map
3. Improve the error message when hitting the limit to mention --dynamic-config-value or link to docs (though this specific limit isn't dynamic config, it's a server config)

[amit-writes-code]

I think I can pick this one, will start with #3 if that's fine