docs: clarify scope of databricks_grant, reword reference to principals

[tlecomte]

Changes

Reword the following documentation pages:

• databricks_grant: it looks like the introduction text was copied from databricks_grants (plural), so reword to make it clearer that databricks_grant applies to a single securable+principal combination
• databricks_grant and databricks_grants: a minor reword on users and groups are referred to as principals

Tests

Look at the markdown renders.

[github-actions]

If integration tests don't run automatically, an authorized user can run them manually by following the instructions below:

Trigger:
go/deco-tests-run/terraform

Inputs:

• PR number: 5182
• Commit SHA: 2012bde856b1044586b60901fc391eb97f663415

Checks will be approved automatically on success.

[Copilot]

Pull Request Overview

This PR improves the clarity of documentation for Unity Catalog grant resources by clarifying the scope of databricks_grant and standardizing terminology around principals.

• Rewording the introductory text for databricks_grant to clarify it manages grants for a single securable+principal combination
• Standardizing the reference to users and groups as "principals" across both grant documentation pages
• Adding changelog entry for the documentation improvements

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
docs/resources/grant.md	Clarified that databricks_grant is authoritative for a specific securable+principal pair, and standardized principal terminology
docs/resources/grants.md	Standardized the phrasing around principals from "called principals in general" to "referred to as principals"
NEXT_CHANGELOG.md	Added changelog entry documenting the documentation improvements

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.