Improved metadata binding parsing and validation.

[kshyju]

Improving how metadata binding is being read and used. Handles both worker indexing and host indexing cases.

Pull request checklist

IMPORTANT: Currently, changes must be backported to the in-proc branch to be included in Core Tools and non-Flex deployments.

• Backporting to the in-proc branch is not required
  • Otherwise: Link to backporting PR
• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr - will follow
• My changes do not require diagnostic events changes
  • Otherwise: I have added/updated all related diagnostic events and their documentation (Documentation issue linked to PR)
• I have added all required tests (Unit tests, E2E tests)

[kshyju]

Had offline sync with @surgupta-msft and agreed to mask only the "connection" binding value.

[Copilot]

Pull Request Overview

This PR improves metadata binding parsing and validation by implementing sanitization of sensitive data (specifically connection strings) in function metadata bindings. The changes handle both worker indexing and host indexing scenarios to prevent exposure of sensitive credentials in logs or error messages.

• Introduces a new MetadataJsonHelper class with methods to sanitize sensitive properties in JSON objects
• Updates both WorkerFunctionMetadataProvider and HostFunctionMetadataProvider to use the sanitization logic
• Adds comprehensive test coverage for the new sanitization functionality

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/WebJobs.Script/Host/MetadataJsonHelper.cs	New helper class providing JSON sanitization methods for sensitive metadata properties
src/WebJobs.Script/ScriptConstants.cs	Adds constant defining sensitive binding property names (connection)
src/WebJobs.Script/Host/WorkerFunctionMetadataProvider.cs	Updates binding validation to use sanitization and removes unused serializer settings
src/WebJobs.Script/Host/HostFunctionMetadataProvider.cs	Integrates sanitization into metadata parsing for host functions
src/WebJobs.Script.WebHost/Extensions/FunctionMetadataExtensions.cs	Adds sanitization when reading function configuration from files
test/WebJobs.Script.Tests/MetadataJsonHelperTests.cs	Comprehensive test suite for the new sanitization functionality
test/WebJobs.Script.Tests/WorkerFunctionMetadataProviderTests.cs	Test ensuring worker provider masks sensitive data correctly
test/WebJobs.Script.Tests/HostFunctionMetadataProviderTests.cs	Test ensuring host provider masks sensitive data correctly
release_notes.md	Documents the metadata binding validation improvement