feat!: add cache service v2, add toolkit patches (#1110)

Serves `github.actions.results.api.v1.CacheService` next to the v1 cache API, sharing its store, plus the subset of the Azure blob protocol the toolkit uploads with. On by default via `cache.v2`, and works with `external_server`.

Clients reach it through two edits in the action's own bundle: the GHES check is opened, and the cache service URL is taken from `ACTIONS_CACHE_URL`.

The same GHES check is what makes the stock `actions/upload-artifact` and `download-artifact` abort on Gitea. Opening it makes them work without the `gitea-upload-artifact` fork, from `[email protected]` on.

Verified against 118 real bundles, every major version of 16 actions: 92 patched, the rest deliberately left alone, and every patched bundle checked with `node --check`. Also end to end against pinned `actions/[email protected]` with an unreachable results URL, so only the patch can make the cache work.

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Co-authored-by: silverwind <[email protected]>
Co-authored-by: bircni <[email protected]>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1110
Reviewed-by: silverwind <[email protected]>

internal/app/cmd/exec.go

@@ -132,6 +132,8 @@ func (i *executeArgs) LoadEnvs() map[string]string {
 	_ = readEnvs(i.Envfile(), envs)
 
 	envs["ACTIONS_CACHE_URL"] = i.cacheHandler.ExternalURL() + "/"
+	// The same server answers the cache service v2 API, so let the actions reach it.
+	envs[runner.CacheServiceV2Env] = "true"
 
 	return envs
 }