Mark provenance of SQL via the branded types SafeSqlFragment and
UntrustedSqlFragment. Only SafeSqlFragment should be executed;
UntrustedSqlFragments require some kind of implicit user approval (show
on screen + user has to click something) before they are promoted to
SafeSqlFragment.
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## Summary by CodeRabbit
* **New Features**
* Editor and RLS tester show loading states for inferred/generated SQL
and include a dedicated user SQL editor for safer edits.
* **Refactor**
* Platform-wide SQL handling tightened: snippets and AI-generated SQL
are treated as untrusted/display-only until promoted, improving safety
and consistency.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
## Context
Resolves FE-3077
Related discussion: https://github.com/orgs/supabase/discussions/45233
Verifying the correctness of your RLS policies set up has always been a
gap, as highlighted by a number of GitHub discussions like
[here](https://github.com/orgs/supabase/discussions/12269) and
[here](https://github.com/orgs/supabase/discussions/14401). As such,
we're piloting a dedicated UI for RLS testing (using role impersonation
as the base), in which you'll be able to
- Run a SQL query as a user (not logged in / logged in - this is the
role impersonation part)
- See which RLS policies are being evaluated as part of the query
- And hopefully be able to debug which policies are not set up correctly
Changes are currently set as a feature preview - and we'll iterate as we
get feedback from everyone 🙂🙏
<img width="613" height="957" alt="image"
src="https://github.com/user-attachments/assets/83c37f8a-28fc-43b3-b0ff-e28571d8710c"
/>
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **New Features**
* RLS Tester: run queries as anon or authenticated users, view inferred
SQL, per-table policy summaries, and data previews of accessible rows.
* UI preview: new RLS Tester preview card and modal with opt-in toggle;
RLS Tester sheet with role/user selector and query editor.
* SQLEditor: “Explain” tab is always visible.
* **Chores**
* Added supporting API endpoints, background checks for table RLS
status, and a local-storage flag to persist the preview opt-in.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Charis