Add comprehensive README.md

[Copilot]

No root-level README existed; the repo had no onboarding path for new contributors or operators.

What's added (README.md, 482 lines)

• Overview & features — purpose of the app, feature table
• Architecture — ASCII layer diagram (API → Application → Domain → Infrastructure), project-role table, key patterns (Repository, UoW, DI, DTO/AutoMapper, FluentValidation, exception middleware), annotated data-flow example
• Setup & running — dotnet restore → dotnet watch run (backend on localhost:5210); static-serve instructions for the frontend; note on API_BASE_URL constant in script.js
• Tests — dotnet test invocation with Release config and verbose flag
• Configuration — appsettings.json snippet, env var reference table, User Secrets for local dev, Azure Key Vault guidance for production; explicit warning about the empty .env file
• API reference — all five controllers with method/path/description tables, JSON request body examples, query-param tables, status/grade enum values, health check, Swagger UI location (/)
• Deployment — CI/CD workflow summary (build-test → deploy jobs), required AZURE_WEBAPP_PUBLISH_PROFILE secret, AZURE_WEBAPP_NAME placeholder callout, manual az webapp deploy snippet, production checklist (env, DB provider swap, HTTPS/HSTS)
• Troubleshooting — port conflicts, missing SDK, CORS errors, test rebuild, in-memory seed data lifecycle, deployment failures, log tailing
• Links to existing AI_DEVOPS_DEMO_PLAN.md and DEMO_QUICK_REFERENCE.md

Original prompt

Create comprehensive application documentation for the CanarysPlayground/CourseApplication repository.

Documentation should:

• Explain what the application does and its main features.
• Describe the architecture at a high level (major modules/services, data flow).
• Provide setup and installation instructions, including prerequisites.
• Include how to run the app locally (dev) and how to run tests.
• Document configuration (env vars / settings files) and any secrets handling.
• Provide API documentation if applicable (endpoints, request/response examples).
• Include deployment instructions if present (Docker, CI/CD, hosting).
• Add a basic troubleshooting section.

Implementation requirements:

• Add or update README.md at the repo root.
• If the repo already has docs, consolidate and link them from the README.
• Ensure commands are accurate for the repository’s language/framework.

Repository: CanarysPlayground/CourseApplication
Base branch: main

The following is the prior conversation context from the user's chat exploration (may be truncated):

User: write a function on factorial

Assistant: - Here’s a simple Python function to compute a factorial (with input validation).

def factorial(n: int) -> int:
    """
    Return n! (factorial of n) for a non-negative integer n.

    Raises:
        TypeError: if n is not an int
        ValueError: if n is negative
    """
    if not isinstance(n, int):
        raise TypeError("n must be an integer")
    if n < 0:
        raise ValueError("n must be non-negative")

    result = 1
    for k in range(2, n + 1):
        result *= k
    return result


# Example usage:
# print(factorial(0))  # 1
# print(factorial(5))  # 120

• If you want a recursive version instead (or one that supports big ints / memoization), tell me your preference.

User: give me the documentation of this application

Assistant: - I’m waiting for you to accept or reject the tool permission prompt; once you respond, I can continue generating the application documentation.

This pull request was created from Copilot chat.

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