Use SandboxedEnvironment for Template

[slister1001]

Description

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Testing Guidelines

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[Copilot]

Pull Request Overview

This pull request introduces conditional usage of jinja2’s SandboxedEnvironment for template rendering based on the PF_USE_SANDBOX_FOR_JINJA environment variable, ensuring safer template execution. Key changes include:

• Updating CLI, core utilities, static web blueprint, and connection utilities to use SandboxedEnvironment when enabled.
• Wrapping template rendering in try/except blocks to capture and re-raise errors as UserErrorException.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
src/promptflow-devkit/promptflow/_cli/_pf/_init_entry_generators.py	Adds sandboxed template loading with conditional environment variable check and error handling.
src/promptflow-core/promptflow/core/_utils.py	Updates the render function to support sandboxed templates and wraps rendering logic in a try/except block.
src/promptflow-core/promptflow/core/_serving/v1/blueprint/static_web_blueprint.py	Implements conditional sandboxed rendering of static web templates with error capturing.
src/promptflow-core/promptflow/_utils/connection_utils.py	Modifies connection template generation to use a sandboxed jinja2 environment, including error handling.