fix: job container, daemon startup, action cache and exec fixes (#1294)

- Keep `GITHUB_ENV`, `GITHUB_OUTPUT`, `GITHUB_STATE` and `GITHUB_PATH` when a job times out or is cancelled, so post steps still get their state
- Retry the startup Declare while Gitea is unreachable instead of exiting, still failing fast on rejected registrations, auth and misconfiguration
- Reuse a local image when a platform variant such as `linux/arm/v7` is requested instead of pulling again
- Read `PATH` from the created job container so cross-architecture jobs get tool paths for the right architecture
- Extract action copies relative to the act volume so they never cross an image's `/var/run` symlink, which rootless Podman rejects
- Keep the job container's entrypoint when container options set `--entrypoint`, warning instead of appending it to the keep-alive command
- Lock action cache entries across runner processes that share a cache directory
- `exec`: omit `GITHUB_SERVER_URL` and `GITHUB_API_URL` without `--gitea-instance` instead of exporting a bare `https://`, and read owner and repository from any origin remote

Reviewed-on: https://gitea.com/gitea/runner/pulls/1294
Reviewed-by: bircni <[email protected]>
Co-authored-by: silverwind <[email protected]>

act/runner/action_test.go

@@ -143,6 +143,7 @@ runs:
 }
 
 func TestActionRunner(t *testing.T) {
+	t.Chdir(t.TempDir())
 	table := []struct {
 		name        string
 		step        actionStep
@@ -366,7 +367,10 @@ func TestMaybeCopyToActionDirHoldsCloneLock(t *testing.T) {
 
 	peerAcquired := make(chan struct{})
 	go func() {
-		unlock := git.AcquireCloneLock(actionDir)
+		unlock, err := git.AcquireCloneLock(t.Context(), actionDir)
+		if !assert.NoError(t, err) {
+			return
+		}
 		close(peerAcquired)
 		unlock()
 	}()
@@ -400,7 +404,9 @@ func TestMaybeCopyToActionDirHoldsCloneLock(t *testing.T) {
 func TestExecAsDockerHoldsCloneLockForRemoteUncached(t *testing.T) {
 	actionDir := t.TempDir()
 
-	unlockOnce := sync.OnceFunc(git.AcquireCloneLock(actionDir))
+	unlock, err := git.AcquireCloneLock(t.Context(), actionDir)
+	require.NoError(t, err)
+	unlockOnce := sync.OnceFunc(unlock)
 	defer unlockOnce()
 
 	innerEntered := make(chan struct{})