feat(api): add BudgetsController with status, create, update endpoints

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

MoneyMap/Controllers/BudgetsController.cs

@@ -0,0 +1,103 @@
+using Microsoft.AspNetCore.Mvc;
+using MoneyMap.Models;
+using MoneyMap.Services;
+
+namespace MoneyMap.Controllers;
+
+[ApiController]
+[Route("api/[controller]")]
+public class BudgetsController : ControllerBase
+{
+    private readonly IBudgetService _budgetService;
+
+    public BudgetsController(IBudgetService budgetService) => _budgetService = budgetService;
+
+    [HttpGet("status")]
+    public async Task<IActionResult> GetStatus([FromQuery] string? asOfDate = null)
+    {
+        DateTime? date = null;
+        if (!string.IsNullOrWhiteSpace(asOfDate) && DateTime.TryParse(asOfDate, out var parsed))
+            date = parsed;
+
+        var statuses = await _budgetService.GetAllBudgetStatusesAsync(date);
+
+        var result = statuses.Select(s => new
+        {
+            s.Budget.Id,
+            Category = s.Budget.DisplayName,
+            s.Budget.Amount,
+            Period = s.Budget.Period.ToString(),
+            s.PeriodStart,
+            s.PeriodEnd,
+            s.Spent,
+            s.Remaining,
+            PercentUsed = Math.Round(s.PercentUsed, 1),
+            s.IsOverBudget
+        }).ToList();
+
+        return Ok(result);
+    }
+
+    [HttpPost]
+    public async Task<IActionResult> Create([FromBody] CreateBudgetRequest request)
+    {
+        if (!Enum.TryParse<BudgetPeriod>(request.Period, true, out var budgetPeriod))
+            return BadRequest(new { message = $"Invalid period '{request.Period}'. Must be Weekly, Monthly, or Yearly." });
+
+        if (!DateTime.TryParse(request.StartDate, out var startDate))
+            return BadRequest(new { message = "Invalid start date format" });
+
+        var budget = new Budget
+        {
+            Category = request.Category,
+            Amount = request.Amount,
+            Period = budgetPeriod,
+            StartDate = startDate,
+            IsActive = true
+        };
+
+        var result = await _budgetService.CreateBudgetAsync(budget);
+
+        return Ok(new { result.Success, result.Message, BudgetId = budget.Id });
+    }
+
+    [HttpPut("{id}")]
+    public async Task<IActionResult> Update(int id, [FromBody] UpdateBudgetRequest request)
+    {
+        var budget = await _budgetService.GetBudgetByIdAsync(id);
+        if (budget == null)
+            return NotFound(new { message = "Budget not found" });
+
+        if (request.Amount.HasValue)
+            budget.Amount = request.Amount.Value;
+
+        if (!string.IsNullOrWhiteSpace(request.Period))
+        {
+            if (!Enum.TryParse<BudgetPeriod>(request.Period, true, out var budgetPeriod))
+                return BadRequest(new { message = $"Invalid period '{request.Period}'. Must be Weekly, Monthly, or Yearly." });
+            budget.Period = budgetPeriod;
+        }
+
+        if (request.IsActive.HasValue)
+            budget.IsActive = request.IsActive.Value;
+
+        var result = await _budgetService.UpdateBudgetAsync(budget);
+
+        return Ok(new { result.Success, result.Message });
+    }
+}
+
+public class CreateBudgetRequest
+{
+    public string? Category { get; set; }
+    public decimal Amount { get; set; }
+    public string Period { get; set; } = "";
+    public string StartDate { get; set; } = "";
+}
+
+public class UpdateBudgetRequest
+{
+    public decimal? Amount { get; set; }
+    public string? Period { get; set; }
+    public bool? IsActive { get; set; }
+}