test: make TestRunEvent integration suite runnable locally (#987)

The `TestRunEvent*` integration tests are skipped in CI (`make test` runs `-short`), which hid several breakages that make them fail when run locally:

- `runTest` built the runner `Config` without `ContainerMaxLifetime`, so the job container ran `/bin/sleep 0` and exited immediately — every step failed with "container is not running". Set it to 1h.
- The root `.gitignore`'s unscoped `.env` and `dist` rules shadowed fixtures under `testdata/`. Anchored `dist` → `/dist` (the goreleaser output) and un-ignored `testdata/secrets/.env`.
- Added the missing `testdata/secrets/.env` fixture for `TestRunEventSecrets`.
- The `node24` local action referenced a `dist/index.js` bundle that was never committed (and was gitignored). Made the fixture self-contained (dependency-free ESM, `main: index.js`) so it runs without an `ncc` build. If you'd rather keep the `@actions/core`-based action and commit the built bundle instead, happy to switch.

Network-dependent subtests (remote `uses:`/composite actions) are out of scope.

---
This PR was written with the help of Claude Opus 4.7

---------

Co-authored-by: Nicolas <bircni@icloud.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-on: https://gitea.com/gitea/runner/pulls/987
Reviewed-by: Nicolas <bircni@icloud.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-committed-by: silverwind <me@silverwind.io>

act/runner/runner_test.go

@@ -15,6 +15,7 @@ import (
 	"runtime"
 	"strings"
 	"testing"
+	"time"
 
 	"gitea.com/gitea/runner/act/common"
 	"gitea.com/gitea/runner/act/model"
@@ -192,6 +193,7 @@ func (j *TestJobFileInfo) runTest(ctx context.Context, t *testing.T, cfg *Config
 		Inputs:                cfg.Inputs,
 		GitHubInstance:        "github.com",
 		ContainerArchitecture: cfg.ContainerArchitecture,
+		ContainerMaxLifetime:  time.Hour,
 		Matrix:                cfg.Matrix,
 		ActionCache:           cfg.ActionCache,
 	}