refactor+feat(backend): ChargeableCharConfig por ProductType + Reactivate + Delete endpoints (PRC-001)

Part A — MedioId → ProductTypeId rename across all C# layers:
  Domain, Application, Infrastructure, API, all test projects.
  Solution was non-compilable after BD refactor (5c1675e); now compiles clean (0 errors).

Part B — PATCH /api/v1/admin/chargeable-chars/{id}/reactivate:
  ReactivateChargeableCharConfigCommand/Handler, SP guard maps 50410/50411/50412
  → ChargeableCharConfigReactivationNotAllowedException(Reason) → HTTP 409.

Part C — DELETE /api/v1/admin/chargeable-chars/{id}:
  DeleteChargeableCharConfigCommand/Handler, physical DELETE on SYSTEM_VERSIONED table.
  KeyNotFoundException → 404 via ExceptionFilter.

Tests: +30 unit tests (TDD RED→GREEN). All 1266 unit tests pass.

src/api/SIGCM2.Api/Controllers/ChargeableCharConfigController.cs

@@ -6,8 +6,10 @@ using SIGCM2.Application.Common;
 using SIGCM2.Application.Pricing.ChargeableChars;
 using SIGCM2.Application.Pricing.ChargeableChars.Create;
 using SIGCM2.Application.Pricing.ChargeableChars.Deactivate;
+using SIGCM2.Application.Pricing.ChargeableChars.Delete;
 using SIGCM2.Application.Pricing.ChargeableChars.GetById;
 using SIGCM2.Application.Pricing.ChargeableChars.List;
+using SIGCM2.Application.Pricing.ChargeableChars.Reactivate;
 using SIGCM2.Application.Pricing.ChargeableChars.SchedulePrice;
 
 namespace SIGCM2.Api.Controllers;
@@ -39,7 +41,7 @@ public sealed class ChargeableCharConfigController : ControllerBase
 
     /// <summary>
     /// Returns a paginated list of ChargeableCharConfig rows.
-    /// Filters: medioId (optional, long?), activeOnly (bool, default true).
+    /// Filters: productTypeId (optional, long?), activeOnly (bool, default true).
     /// Pagination: skip/take model mapped to page/pageSize — or use page/pageSize directly.
     /// Defaults: page=1, pageSize=20. Clamped: pageSize max 200.
     /// </summary>
@@ -49,7 +51,7 @@ public sealed class ChargeableCharConfigController : ControllerBase
     [ProducesResponseType(StatusCodes.Status401Unauthorized)]
     [ProducesResponseType(StatusCodes.Status403Forbidden)]
     public async Task<IActionResult> List(
-        [FromQuery] long? medioId,
+        [FromQuery] long? productTypeId,
         [FromQuery] bool activeOnly = true,
         [FromQuery] int? page = null,
         [FromQuery] int? pageSize = null,
@@ -74,7 +76,7 @@ public sealed class ChargeableCharConfigController : ControllerBase
             resolvedPageSize = Math.Min(pageSize ?? 20, 200);
         }
 
-        var query = new ListChargeableCharConfigQuery(medioId, activeOnly, resolvedPage, resolvedPageSize);
+        var query = new ListChargeableCharConfigQuery(productTypeId, activeOnly, resolvedPage, resolvedPageSize);
         var result = await _dispatcher.Send<ListChargeableCharConfigQuery, PagedResult<ChargeableCharConfigDto>>(query);
         return Ok(result);
     }
@@ -100,7 +102,7 @@ public sealed class ChargeableCharConfigController : ControllerBase
     // ── POST /api/v1/admin/chargeable-chars ───────────────────────────────────
 
     /// <summary>
-    /// Creates a new ChargeableCharConfig row. Closes the current active row for (MedioId, Symbol) if one exists.
+    /// Creates a new ChargeableCharConfig row. Closes the current active row for (ProductTypeId, Symbol) if one exists.
     /// Returns 201 Created with Location header pointing to GET /{id}.
     /// </summary>
     [HttpPost]
@@ -113,7 +115,7 @@ public sealed class ChargeableCharConfigController : ControllerBase
     public async Task<IActionResult> Create([FromBody] CreateChargeableCharConfigRequest request)
     {
         var command = new CreateChargeableCharConfigCommand(
-            request.MedioId,
+            request.ProductTypeId,
             request.Symbol,
             request.Category,
             request.PricePerUnit,
@@ -183,13 +185,57 @@ public sealed class ChargeableCharConfigController : ControllerBase
             new DeactivateChargeableCharConfigCommand(id));
         return Ok(result);
     }
+
+    // ── PATCH /api/v1/admin/chargeable-chars/{id}/reactivate ─────────────────
+
+    /// <summary>
+    /// Reactivates a previously closed ChargeableCharConfig row (undo last deactivation).
+    /// Guard rules (enforced by SP):
+    ///   - ALREADY_ACTIVE: target row is already active → 409
+    ///   - VIGENTE_EXISTS: a different active row exists for (ProductTypeId, Symbol) → 409
+    ///   - POSTERIOR_ROWS_EXIST: rows with higher ValidFrom exist after the target → 409
+    /// </summary>
+    [HttpPatch("{id:long}/reactivate")]
+    [RequirePermission("tasacion:caracteres_especiales:gestionar")]
+    [ProducesResponseType(typeof(ReactivateChargeableCharConfigResponse), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status401Unauthorized)]
+    [ProducesResponseType(StatusCodes.Status403Forbidden)]
+    [ProducesResponseType(StatusCodes.Status409Conflict)]
+    public async Task<IActionResult> Reactivate([FromRoute] long id)
+    {
+        var result = await _dispatcher.Send<ReactivateChargeableCharConfigCommand, ReactivateChargeableCharConfigResponse>(
+            new ReactivateChargeableCharConfigCommand(id));
+        return Ok(result);
+    }
+
+    // ── DELETE /api/v1/admin/chargeable-chars/{id} ───────────────────────────
+
+    /// <summary>
+    /// Deletes a ChargeableCharConfig row.
+    /// NOTE: With SYSTEM_VERSIONING ON, the row is moved to the history table (temporal audit preserved).
+    /// The row disappears from all current-state queries.
+    /// Guard for "used in invoicing" is deferred to FAC-001 followup issue.
+    /// Returns 200 + { id } consistent with the Deactivate pattern.
+    /// </summary>
+    [HttpDelete("{id:long}")]
+    [RequirePermission("tasacion:caracteres_especiales:gestionar")]
+    [ProducesResponseType(typeof(DeleteChargeableCharConfigResponse), StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status401Unauthorized)]
+    [ProducesResponseType(StatusCodes.Status403Forbidden)]
+    [ProducesResponseType(StatusCodes.Status404NotFound)]
+    public async Task<IActionResult> Delete([FromRoute] long id)
+    {
+        var result = await _dispatcher.Send<DeleteChargeableCharConfigCommand, DeleteChargeableCharConfigResponse>(
+            new DeleteChargeableCharConfigCommand(id));
+        return Ok(result);
+    }
 }
 
 // ── Request body records ──────────────────────────────────────────────────────
 
 /// <summary>PRC-001: Create ChargeableCharConfig request body.</summary>
 public sealed record CreateChargeableCharConfigRequest(
-    long? MedioId,
+    long? ProductTypeId,
     string Symbol,
     string Category,
     decimal PricePerUnit,