[AZ-447] autodev Steps 1-4 baseline: docs, tests, refactor specs

Captures the full output of autodev existing-code Phase A through
Step 4 (Code Testability Revision) for the Azaion UI workspace:

- Step 1 Document: _docs/02_document/ (FINAL_report, architecture,
  glossary, components/, modules/, diagrams/, system-flows,
  module-layout) plus _docs/00_problem/ + _docs/01_solution/ +
  _docs/legacy/ + _docs/how_to_test + README.
- Step 2 Architecture Baseline: architecture_compliance_baseline.md.
- Step 3 Test Spec: _docs/02_document/tests/ (environment,
  test-data, blackbox/performance/resilience/security/
  resource-limit tests, traceability-matrix), enum_spec_snapshot,
  expected_results/results_report.md (98 rows), plus the
  run-tests.sh + run-performance-tests.sh runners.
- Step 4 Code Testability Revision: 01-testability-refactoring/
  run dir (list-of-changes C01-C07, deferred_to_refactor,
  analysis/research_findings + refactoring_roadmap) and the 7
  child task specs AZ-448..AZ-454 under _docs/02_tasks/todo/
  plus _dependencies_table.md.
- _docs/_autodev_state.md pins the cursor at Step 4 / refactor
  Phase 4 entry so /autodev resumes cleanly.

Epic AZ-447 (UI testability gates) tracks the 7 child tasks that
will land in subsequent commits.

Co-authored-by: Cursor <cursoragent@cursor.com>

_docs/02_document/components/04_login/description.md

@@ -0,0 +1,48 @@
+# 04 — Login
+
+## 1. High-Level Overview
+
+**Purpose**: The single public route `/login`. Renders the credential form and triggers `useAuth().login(...)`.
+
+**Architectural Pattern**: Single-page feature module with one entry component.
+
+**Upstream dependencies**: `02_auth` (`useAuth().login`).
+
+**Downstream consumers**: `10_app-shell` (routed at `/login`).
+
+## 2. Internal Interfaces
+
+| Export | Notes |
+|--------|-------|
+| `LoginPage()` | Form: username + password + submit. Calls `useAuth().login({ username, password })` and on success navigates to `/flights`. Error state shown inline. |
+
+## 5. Implementation Details
+
+- "Theatrical" unlock animation (`runUnlockSequence`, 4 × 600 ms) plays on success before navigation. Documented in Step 5 solution.md as a UX choice, not a bug.
+- No "remember me" / persistent-session toggle.
+- No SSO integration.
+- No password-strength feedback or recovery link.
+
+**State Management**: Local component state only.
+
+**Key Dependencies**: `react-router-dom` (`useNavigate`), `react-i18next`.
+
+## 7. Caveats & Edge Cases
+
+- **2.4 s artificial delay** post-login (Step 5 doc note).
+- **No CSRF token** in the login POST body — server is expected to validate the same-site cookie pattern; document in `security_approach.md` (Step 6).
+- **No rate-limit feedback** — server returns `429` with no specific UI handling beyond a generic `alert`.
+
+## 8. Dependency Graph
+
+**Must be implemented after**: `02_auth`.
+
+**Can be implemented in parallel with**: every feature page (`05_flights` … `09_settings`).
+
+**Blocks**: nothing.
+
+## Module Inventory
+
+| Path | Module Doc |
+|------|------------|
+| `src/features/login/LoginPage.tsx` | `_docs/02_document/modules/src__features__login__LoginPage.md` |