feat: add frontend development guidelines and structure documentation

- Introduced API guidelines for interface contracts and request handling.
- Added design tokens usage guidelines for consistent styling across the project.
- Established DTO guidelines for defining request parameters and response data types.
- Created frontend structure guidelines to clarify directory organization and code placement rules.
- Compiled a comprehensive frontend development guideline document covering various aspects of the development process.
- Implemented quality guidelines to ensure code maintainability and adherence to best practices.

AI-RD-Workflow/20-skills/test-case-generate/SKILL.md

@@ -0,0 +1,38 @@
+---
+name: test-case-generate
+description: Generate test plans and test cases from user requirements, engineering requirements, detailed design, and implementation tasks. Use when Codex needs to produce traceable positive, negative, boundary, regression, and risk-based tests.
+---
+
+# Test Case Generate
+
+Generate test artifacts from requirements and design.
+
+## Inputs
+
+- UR, RA, SA.
+- OR, DR.
+- DS and TASK.
+- Existing test conventions if available.
+
+## Process
+
+1. Identify test scope and non-scope.
+2. Build a test plan with strategy, environment, data, entry criteria, and exit criteria.
+3. Generate test cases for main, exception, boundary, permission, compatibility, and regression paths.
+4. Map each test case to source requirement or design IDs.
+5. Mark untestable or unclear requirements.
+
+## Output
+
+Generate:
+
+- TP.
+- TC list.
+- Coverage gaps.
+- Risk-based regression suggestions.
+
+## Quality Bar
+
+- Each critical requirement has coverage.
+- Expected results are concrete.
+- Test data and preconditions are explicit.