🧪 test: add JWT secret rotation BDD scenarios and step implementations (#12)

✨ merge: implement JWT secret rotation with BDD scenario isolation

- Implement JWT secret rotation mechanism (closes #8)
- Add per-scenario state isolation for BDD tests (closes #14)
- Validate password reset workflow via BDD tests (closes #7)
- Fix port conflicts in test validation
- Add state tracer for debugging test execution
- Document BDD isolation strategies in ADR 0025
- Fix PostgreSQL configuration environment variables

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>
Co-authored-by: Gabriel Radureau <arcodange@gmail.com>
Co-committed-by: Gabriel Radureau <arcodange@gmail.com>

.vibe/skills/bdd-testing/references/TEST_SERVER.md

@@ -351,7 +351,10 @@ func TestBDD(t *testing.T) {
         Options: &godog.Options{
             Format:   "progress",
             Paths:    []string{"."},
-            TestingT: t,
+            TestingT:      t,
+			Strict: true,
+			Randomize:     -1,
+			StopOnFailure: true,
             // Enable parallel execution
             Concurrency: 4,  // Number of parallel scenarios
         },