Support repo-registration as a second enablement path for project-entry caching

Configuration-cache store/restore is now enabled when EITHER a valid Develocity
JWT OR per-repo registration (a GitHub App installation that accepted the T&C) is
present. The gate itself lives in the vendored gradle-actions-caching library
(refreshed to 0.9.1); this repo wires up the reporting and notice.

- ProjectCacheStatus: 'trial-not-licensed' -> 'not-registered'.
- caching-report: render the 'not-registered' line with a /register link, and add
  renderProjectCacheNotice() for a prominent core.notice.
- setup-gradle: emit the notice from complete() only when withheld via the
  registration path; quiet when enabled by either path.
- Refresh vendored gradle-actions-caching to 0.9.1.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

sources/src/setup-gradle.ts

@@ -9,6 +9,7 @@ import {setupToken} from './develocity/short-lived-token'
 
 import {loadBuildResults, markBuildResultsProcessed} from './build-results'
 import {getCacheService, getProviderNote} from './cache-service-loader'
+import {renderProjectCacheNotice} from './caching-report'
 import {CacheOptions} from './cache-service'
 import {
     DevelocityConfig,
@@ -85,6 +86,14 @@ export async function complete(
         buildResults,
         cacheOptionsFrom(cacheConfig, develocityServerUrl, cacheToken)
     )
+
+    // Surface a prominent notice (with the /register link) only when advanced caching was withheld
+    // because the repo is not registered; stay quiet when enabled by either path.
+    const registrationNotice = renderProjectCacheNotice(cacheReport.projectCache)
+    if (registrationNotice) {
+        core.notice(registrationNotice)
+    }
+
     await jobSummary.generateJobSummary(buildResults, cacheReport, getProviderNote(cacheConfig), summaryConfig)
 
     markBuildResultsProcessed()