Promote AllowToolcacheInput feature

[mbg]

This feature has been rolled out for some time now. This PR removes the FF and makes the behaviour that was guarded by it the default.

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?

Workflow types:

• Managed - Impacts users with dynamic workflows (Default Setup, Code Quality, ...).

Products:

• Code Scanning - The changes impact analyses when analysis-kinds: code-scanning.
• Code Quality - The changes impact analyses when analysis-kinds: code-quality.
• Other first-party - The changes impact other first-party analyses.

Environments:

• Dotcom - Impacts CodeQL workflows on github.com and/or GitHub Enterprise Cloud with Data Residency.
• GHES - Impacts CodeQL workflows on 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.

Are there any special considerations for merging or releasing this change?

• No special considerations - This change can be merged at any time.

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]

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Pull request overview

Promotes tools: toolcache to default behavior for dynamic workflows and test mode by removing its feature flag.

Changes:

• Removes AllowToolcacheInput configuration.
• Simplifies toolcache eligibility and warning logic.
• Updates unit tests for unconditional availability.

Show a summary per file

File	Description
src/setup-codeql.ts	Removes feature-flag gating.
src/setup-codeql.test.ts	Updates toolcache tests.
src/feature-flags.ts	Removes the promoted flag.
lib/entry-points.js	Generated artifact; excluded from review.

Review details

Files excluded by content exclusion policy (1)

• lib/entry-points.js

• Files reviewed: 3/4 changed files
• Comments generated: 0
• Review effort level: Medium