Extract caching logic into a separate gradle-actions-caching component (#885)

With this change, the caching functionality of `setup-gradle` and
`dependency-submission` is now provided by `gradle-actions-caching`, a
closed-source library distributed under our [Terms of
Use](https://gradle.com/legal/terms-of-use/). The rest of the action
implementation remains open source.

Using `setup-gradle` or `dependency-submission` with caching enabled
involves loading and using the `gradle-actions-caching` component,
requiring acceptance of the [Terms of
Use](https://gradle.com/legal/terms-of-use/). There are no functional
changes to caching provided by these actions: all workflows will
continue to function as before.

The non-caching aspects of action implementation remain open source. By
running these actions with caching disabled they can be used without
ever loading `gradle-actions-caching` or accepting the license terms.

Supporting the caching infrastructure in this project requires a
substantial engineering investment by Gradle Technologies, which we can
sustain thanks to Develocity, our commercial offering. Caching
technologies are a core part of the Develocity offering, and the caching
in `setup-gradle` fits squarely in that space.

This licensing change lets us continue to build advanced capabilities
that go beyond what we would offer as open source. Proper
production-ready Configuration Cache support will be the first
capability. Improving build performance for self-hosted runners will
follow.

We may introduce functionality restrictions in future updates. However,
caching functionality will remain free for public repositories.
We have a long-standing commitment to open source, as maintainers of
Gradle Build Tool, and by [sponsoring the open source
community](https://gradle.com/oss-sponsored-by-develocity/) with free
Develocity licenses. Public repositories are primarily used by open
source projects, and we remain committed to supporting them.

- Implementation of caching logic to save and restore Gradle User Home
content has been removed, replaced by the `gradle-actions-caching`
component.
- The `@actions/caching` library is still used to cache Gradle
distributions that are downloaded and provisioned by `setup-gradle`.
This PR updates to the latest version of `@actions/caching`, and removes
the patch that is no longer required.
- License notices are now displayed in documentation, logs and the
generated Job Summary.

sources/package.json

@@ -5,7 +5,6 @@
   "type": "module",
   "description": "Execute Gradle Build",
   "scripts": {
-    "postinstall": "patch-package",
     "prettier-write": "prettier --write 'src/**/*.ts'",
     "prettier-check": "prettier --check 'src/**/*.ts'",
     "lint": "eslint 'src/**/*.ts'",
@@ -37,7 +36,7 @@
   },
   "dependencies": {
     "@actions/artifact": "6.1.0",
-    "@actions/cache": "4.0.5",
+    "@actions/cache": "6.0.0",
     "@actions/core": "3.0.0",
     "@actions/exec": "3.0.0",
     "@actions/github": "9.0.0",
@@ -66,7 +65,6 @@
     "jest": "30.3.0",
     "nock": "15.0.0",
     "npm-run-all": "4.1.5",
-    "patch-package": "8.0.1",
     "prettier": "3.8.1",
     "ts-jest": "29.4.6",
     "typescript": "5.9.3"