feat(dispatch): implement dispatch-workflow.sh with dispatch, poll, and timeout

Add dispatch-workflow.sh script that dispatches a Gitea workflow
in another repository and polls synchronously for completion.
Refactor mock-api.sh to use Python3 HTTP server with sequence
support, enabling stateful poll-response simulation in tests.

tests/features/step_definitions/test-execution.steps.js

@@ -0,0 +1,120 @@
+const { execSync, spawn } = require('child_process');
+const { When, Then, Given } = require('@cucumber/cucumber');
+const fs = require('fs');
+const path = require('path');
+const os = require('os');
+
+const PROJECT_ROOT = path.resolve(__dirname, '..', '..', '..');
+const MOCK_SERVER = path.join(PROJECT_ROOT, 'tests', 'helpers', 'mock-server.py');
+const DISPATCH_SCRIPT = path.join(PROJECT_ROOT, 'scripts', 'dispatch-workflow.sh');
+
+function bash(cmd) {
+  try {
+    const out = execSync(`bash -c ${JSON.stringify(cmd)}`, {
+      cwd: PROJECT_ROOT,
+      encoding: 'utf-8',
+      stdio: ['pipe', 'pipe', 'pipe'],
+    });
+    return { status: 0, stdout: out };
+  } catch (e) {
+    return { status: e.status, stdout: e.stdout || '', stderr: e.stderr || '' };
+  }
+}
+
+function envBlock() {
+  return [
+    'export GITEA_API_URL="http://localhost:18080"',
+    'export GITEA_TOKEN="test-token-abc123"',
+    'export DISPATCH_POLL_INTERVAL="0.1"',
+  ].join('; ');
+}
+
+function setupMock(seqJson) {
+  execSync('pkill -9 -f mock-server 2>/dev/null || true', { stdio: 'ignore' });
+  execSync('sleep 0.4', { stdio: 'ignore' });
+
+  const seqFile = path.join(os.tmpdir(), `cucumber_seq_${Date.now()}.json`);
+  fs.writeFileSync(seqFile, seqJson);
+  const idxFile = `${seqFile}.idx`;
+  fs.writeFileSync(idxFile, '0');
+
+  const reqFile = path.join(os.tmpdir(), `cucumber_req_${Date.now()}.log`);
+  const configFile = path.join(os.tmpdir(), `cucumber_cfg_${Date.now()}.txt`);
+  fs.writeFileSync(configFile, `SEQUENCE\n${seqJson}\n${idxFile}`);
+
+  const proc = spawn('python3', [MOCK_SERVER, '18080', configFile, reqFile], {
+    cwd: PROJECT_ROOT,
+    detached: true,
+    stdio: 'ignore',
+  });
+  proc.unref();
+  this._mockProc = proc;
+
+  for (let i = 0; i < 20; i++) {
+    try {
+      execSync('curl -s --max-time 1 http://localhost:18080/', { stdio: 'ignore' });
+      fs.writeFileSync(idxFile, '0');
+      return;
+    } catch (_) {}
+    execSync('sleep 0.1', { stdio: 'ignore' });
+  }
+  throw new Error('Mock failed to start');
+}
+
+function runDispatch(args) {
+  return bash(`${envBlock()}; bash "${DISPATCH_SCRIPT}" ${args}`);
+}
+
+Given('a deployment has completed in the target environment', function () {
+});
+
+Given('the test project repository exists with test definitions', function () {
+});
+
+When('a test workflow is dispatched to a test project', function () {
+  setupMock(JSON.stringify([
+    { code: 201 },
+    { code: 200, body: { workflow_runs: [{ id: 1, status: 'running' }] } },
+    { code: 200, body: { id: 1, status: 'completed', conclusion: 'success' } },
+  ]));
+  const r = runDispatch('"test-owner/test-repo" "test.yml" "main" \'{"version":"1.2.3"}\'');
+  this.dispatchResult = r.status;
+});
+
+Then('the pipeline waits until the test workflow finishes', function () {
+  if (this.dispatchResult !== 0) throw new Error(`Expected 0, got ${this.dispatchResult}`);
+});
+
+Then('the pipeline continues only after receiving a success result', function () {
+  if (this.dispatchResult !== 0) throw new Error('Expected pipeline to continue after success');
+});
+
+When('a test workflow is dispatched and the tests fail', function () {
+  setupMock(JSON.stringify([
+    { code: 201 },
+    { code: 200, body: { workflow_runs: [{ id: 1, status: 'running' }] } },
+    { code: 200, body: { id: 1, status: 'completed', conclusion: 'failure' } },
+  ]));
+  const r = runDispatch('"test-owner/test-repo" "test.yml" "main" \'{"version":"1.2.3"}\'');
+  this.dispatchResult = r.status;
+});
+
+Then('the calling pipeline reports failure', function () {
+  if (this.dispatchResult !== 1) throw new Error(`Expected failure exit 1, got ${this.dispatchResult}`);
+});
+
+When('a test workflow is dispatched but does not finish within the allowed time', function () {
+  setupMock(JSON.stringify([
+    { code: 201 },
+    { code: 200, body: { workflow_runs: [{ id: 1, status: 'running' }] } },
+    { code: 200, body: { id: 1, status: 'running' } },
+    { code: 200, body: { id: 1, status: 'running' } },
+    { code: 200, body: { id: 1, status: 'running' } },
+  ]));
+  const r = runDispatch('"test-owner/test-repo" "test.yml" "main" \'{"version":"1.2.3"}\' "0.001"');
+  this.dispatchResult = r.status;
+});
+
+Then('the calling pipeline reports a timeout error', function () {
+  if (this.dispatchResult !== 124) throw new Error(`Expected timeout exit 124, got ${this.dispatchResult}`);
+});