fix(tracker): align create-request brief notes to functionalNotes/technicalNotes

The Presentation create-request FunctionalBriefRequest/TechnicalBriefRequest
still used a bare `Notes` key while the UI (sharing the Intake shape) sends
functionalNotes/technicalNotes — so brief notes were dropped on manual create.
Rename to match; verified round-trip (manual create -> notes persist).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: beyondnetPeru

src/apps/tracker-api/Tracker.Presentation/Endpoints/Discovery/InitiativeEndpoints.cs

@@ -246,7 +246,7 @@ public sealed class FunctionalBriefRequest
     public string Objective { get; init; } = string.Empty;
     public List<string>? ExpectedOutcomes { get; init; }
     public string Scope { get; init; } = string.Empty;
-    public string Notes { get; init; } = string.Empty;
+    public string FunctionalNotes { get; init; } = string.Empty;
 }
 
 public sealed class NonFunctionalRequest
@@ -264,7 +264,7 @@ public sealed class TechnicalBriefRequest
     public List<string>? Constraints { get; init; }
     public NonFunctionalRequest? NonFunctional { get; init; }
     public string EstimatedComplexity { get; init; } = string.Empty;
-    public string Notes { get; init; } = string.Empty;
+    public string TechnicalNotes { get; init; } = string.Empty;
 }
 
 public sealed class StakeholderItem
@@ -294,7 +294,7 @@ request is null
                 request.Objective,
                 request.ExpectedOutcomes ?? new List<string>(),
                 request.Scope,
-                request.Notes);
+                request.FunctionalNotes);
 
     public static TechnicalBriefInput? ToInput(this TechnicalBriefRequest? request) =>
         request is null
@@ -311,7 +311,7 @@ request.NonFunctional is null
                         request.NonFunctional.Security,
                         request.NonFunctional.Compliance),
                 request.EstimatedComplexity,
-                request.Notes);
+                request.TechnicalNotes);
 
     public static IReadOnlyList<StakeholderInput>? ToInputs(this List<StakeholderItem>? items) =>
         items?.Select(s => new StakeholderInput(s.Role, s.Identity, s.Resolved)).ToList();