feat: Initialize FastAPI application with Azure authentication and transaction management

- Added .env.example for environment variable configuration.
- Created app initialization files and core settings management.
- Implemented API routers for reporting and transaction endpoints.
- Developed transaction management service with CRUD operations.
- Integrated Azure OAuth for user authentication.
- Designed dashboard view with transaction filtering and display.
- Added Swagger UI documentation with custom dark theme.
- Created static and template files for frontend styling and layout.

app/views/__init__.py

@@ -0,0 +1,5 @@
+from app.views.auth import router as auth_router
+from app.views.dashboard import router as dashboard_router
+from app.views.docs import router as docs_router
+
+__all__ = ["auth_router", "dashboard_router", "docs_router"]

app/views/auth.py

@@ -0,0 +1,46 @@
+from fastapi import APIRouter, HTTPException, Request
+from fastapi.responses import RedirectResponse
+
+from app.core.auth import get_oauth
+from app.core.settings import get_settings
+
+router = APIRouter()
+
+
+@router.get("/login", include_in_schema=False)
+async def login(request: Request):
+    settings = get_settings()
+    if not settings.azure_configured:
+        raise HTTPException(
+            status_code=500,
+            detail=(
+                "Azure Entra ID auth is not configured. Set AZURE_TENANT_ID, "
+                "AZURE_CLIENT_ID, and AZURE_CLIENT_SECRET."
+            ),
+        )
+
+    oauth = get_oauth()
+    redirect_uri = request.url_for("auth_callback")
+    return await oauth.azure.authorize_redirect(request, redirect_uri)
+
+
+@router.get("/auth/callback", include_in_schema=False, name="auth_callback")
+async def auth_callback(request: Request):
+    oauth = get_oauth()
+    token = await oauth.azure.authorize_access_token(request)
+    userinfo = token.get("userinfo")
+    if not userinfo:
+        userinfo = await oauth.azure.parse_id_token(request, token)
+
+    request.session["user"] = {
+        "sub": userinfo.get("sub"),
+        "name": userinfo.get("name") or userinfo.get("preferred_username"),
+        "email": userinfo.get("email") or userinfo.get("preferred_username"),
+    }
+    return RedirectResponse(url="/", status_code=302)
+
+
+@router.get("/logout", include_in_schema=False)
+async def logout(request: Request):
+    request.session.clear()
+    return RedirectResponse(url="/", status_code=302)

app/views/dashboard.py

@@ -0,0 +1,55 @@
+from pathlib import Path
+
+from fastapi import APIRouter, Query, Request
+from fastapi.responses import HTMLResponse, RedirectResponse
+from fastapi.templating import Jinja2Templates
+
+from app.service.recon_service import list_transactions
+
+router = APIRouter()
+
+project_root = Path(__file__).resolve().parents[2]
+templates = Jinja2Templates(directory=str(project_root / "data" / "templates"))
+
+
+@router.get("/", response_class=HTMLResponse, include_in_schema=False)
+async def dashboard(
+    request: Request,
+    recon_job_name: str | None = Query(default=None),
+    as_at_date: str | None = Query(default=None),
+) -> HTMLResponse:
+    user = request.session.get("user")
+    if not user:
+        return RedirectResponse(url="/login", status_code=302)
+
+    transactions = list_transactions()
+
+    if as_at_date:
+        transactions = [item for item in transactions if item.date.isoformat() == as_at_date]
+
+    results = [
+        {
+            "Transaction ID": item.transaction_id,
+            "Date": item.date.isoformat(),
+            "Account": item.account,
+            "Amount": f"{item.amount:,.2f}",
+            "Status": item.status,
+            "Flag": item.flag,
+        }
+        for item in transactions
+    ]
+
+    return templates.TemplateResponse(
+        request=request,
+        name="dashboard.html",
+        context={
+            "request": request,
+            "title": "Recon Ranger Dashboard",
+            "results": results,
+            "user": user,
+            "recon_job_name": recon_job_name,
+            "as_at_date": as_at_date,
+            "prev_cursor": None,
+            "next_cursor": None,
+        },
+    )

app/views/docs.py

@@ -0,0 +1,45 @@
+from fastapi import APIRouter, Request
+from fastapi.openapi.docs import get_swagger_ui_html
+from fastapi.responses import HTMLResponse
+
+router = APIRouter()
+
+
+@router.get("/api/docs", include_in_schema=False)
+async def swagger_ui_dark(request: Request) -> HTMLResponse:
+    base = get_swagger_ui_html(
+        openapi_url=request.app.openapi_url,
+        title="Recon Ranger — API Docs",
+        swagger_css_url="/static/api/swagger-ui.css",
+    )
+    html = base.body.decode()
+
+    html = html.replace(
+        "</head>",
+        (
+            '<link rel="stylesheet" href="/static/css/styles.css">\n'
+            '<link rel="stylesheet" href="/static/api/swagger-dark.css">\n'
+            "<style>.swagger-ui .topbar { display: none; }</style>\n"
+            "</head>"
+        ),
+    )
+
+    nav_html = """
+<header>
+  <nav>
+    <div class=\"menu\">
+      <div class=\"logo\"><a href=\"/\">Recon Ranger</a></div>
+      <ul>
+        <li><a href=\"/\">Home</a></li>
+        <li><a href=\"/api/docs\">API</a></li>
+        <li><a href=\"mailto:someone@example.com\">Contact</a></li>
+      </ul>
+    </div>
+  </nav>
+</header>
+<div style=\"padding-top:70px; position:relative; z-index:1\">
+"""
+    html = html.replace("<body>", "<body>" + nav_html)
+    html = html.replace("</body>", "</div></body>")
+
+    return HTMLResponse(html)