feat: Enable jobs.<job_id>.timeout-minutes and jobs.<job_id>.continue-on-error (#1032)

Two `jobs.<job_id>` workflow syntax fields were parsed from YAML but silently ignored. This PR implements both:

- **`jobs.<job_id>.timeout-minutes`** — applies a context deadline around the entire job execution (container start, pre-steps, main steps, post-steps). Mirrors the existing step-level `evaluateStepTimeout`. Supports expression interpolation (e.g. `${{ env.MY_TIMEOUT }}`).

- **`jobs.<job_id>.continue-on-error`** — evaluates the expression when a job fails. If all failing matrix combinations had `continue-on-error: true`, the job does not cause the workflow run to fail (`handleFailure` skips it), and the tolerated failure reports `success` to dependent jobs through the `needs` context so jobs gated on the default `if: success()` still run (matching GitHub). The "any firm failure wins" rule is serialised under the existing per-job lock, so parallel matrix combinations are safe.

Both features follow the same patterns already used at the step level (`evaluateStepTimeout` / `isContinueOnError` in `act/runner/step.go`).

## Version compatibility

These changes are backward compatible. With mismatched versions the feature degrades silently to the previous behaviour (field ignored) — no errors on either side.

- `timeout-minutes`: runner-only, no server dependency.
- `continue-on-error`: requires both this runner PR and the matching Gitea server PR to take full effect. With only one side updated, the field continues to be ignored.

Related: [Github](https://github.com/go-gitea/gitea/pull/38100)
---------

Co-authored-by: silverwind <2021+silverwind@noreply.gitea.com>
Co-authored-by: silverwind <me@silverwind.io>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1032
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>
Reviewed-by: Zettat123 <39446+zettat123@noreply.gitea.com>

act/runner/runner.go

@@ -250,7 +250,10 @@ func (runner *runnerImpl) NewPlanExecutor(plan *model.Plan) common.Executor {
 							return err
 						}
 
-						return executor(common.WithJobErrorContainer(WithJobLogger(ctx, rc.Run.JobID, jobName, rc.Config, &rc.Masks, matrix)))
+						jobCtx := common.WithJobErrorContainer(WithJobLogger(ctx, rc.Run.JobID, jobName, rc.Config, &rc.Masks, matrix))
+						jobCtx, cancelTimeout := applyJobTimeout(jobCtx, rc, job)
+						defer cancelTimeout()
+						return executor(jobCtx)
 					})
 				}
 				// Run all matrix combinations of this job, then drop its aggregation mutex: the
@@ -305,7 +308,7 @@ func handleFailure(plan *model.Plan) common.Executor {
 	return func(ctx context.Context) error {
 		for _, stage := range plan.Stages {
 			for _, run := range stage.Runs {
-				if run.Job().Result == "failure" {
+				if run.Job().Result == "failure" && !run.Job().ContinueOnError {
 					return fmt.Errorf("Job '%s' failed", run.String())
 				}
 			}