Handle user errors for invalid UserConfigs and missing query files

[mbg]

Classifies two additional types of errors as ConfigurationErrors:

• Invalid config files
• Missing query files

Best reviewed commit-by-commit.

Risk assessment

For internal use only. Please select the risk level of this change:

• Low risk: Changes are fully under feature flags, or have been fully tested and validated in pre-production environments and are highly observable, or are documentation or test only.

Which use cases does this change impact?

• Advanced setup - Impacts users who have custom workflows.
• Default setup - Impacts users who use default setup.
• Code Scanning - Impacts Code Scanning (i.e. analysis-kinds: code-scanning).
• Code Quality - Impacts Code Quality (i.e. analysis-kinds: code-quality).
• GHES - Impacts GitHub Enterprise Server.

How did/will you validate this change?

• Unit tests - I am depending on unit test coverage (i.e. tests in .test.ts files).
• End-to-end tests - I am depending on PR checks (i.e. tests in pr-checks).

If something goes wrong after this change is released, what are the mitigation and rollback strategies?

• Rollback - Change can only be disabled by rolling back the release or releasing a new version with a fix.

How will you know if something goes wrong after this change is released?

• Telemetry - I rely on existing telemetry or have made changes to the telemetry.
  • Dashboards - I will watch relevant dashboards for issues after the release. Consider whether this requires this change to be released at a particular time rather than as part of a regular release.
  • Alerts - New or existing monitors will trip if something goes wrong with this change.

Merge / deployment checklist

• Confirm this change is backwards compatible with existing workflows.
• Consider adding a changelog entry for this change.
• Confirm the readme and docs have been updated if necessary.

[Copilot]

Pull Request Overview

This PR improves error handling for CodeQL configuration by classifying invalid config files and missing query files as ConfigurationErrors. The changes introduce JSON schema validation for config files and better error classification to provide users with clearer feedback when their configurations are malformed.

• Adds JSON schema validation for user config files with structured error reporting
• Expands CLI error classification to include missing query file scenarios
• Updates type definitions to better handle query input formats

Reviewed Changes

Copilot reviewed 17 out of 19 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/error-messages.ts	Adds new error message functions for config file parsing and validation errors
src/db-config-schema.json	Defines comprehensive JSON schema for CodeQL database configuration validation
src/config/db-config.ts	Implements parseUserConfig function with JSON schema validation and updates type definitions
src/config/db-config.test.ts	Adds tests for the new parseUserConfig function covering valid YAML and error cases
src/config-utils.ts	Updates config loading to use the new parseUserConfig function for better error handling
src/cli-errors.ts	Expands error pattern matching to include missing query file scenarios
src/cli-errors.test.ts	Adds test case for unknown query file error classification
src/status-report.ts	Updates query rendering to use new renderQueryInput helper function
lib/*	Generated JavaScript files reflecting the TypeScript changes

[henrymercer]

The comments I made earlier were valid for instructions in general, but the CLI is actually more strict about instructions included in a UserConfig. So I think this is good to go as is.