Add Formula Library ratings, Job Profitability report, and Quote Revision History improvements

- Formula Library ratings: thumbs up/down per company per formula; toggle on/off; sorts by net score; own formulas not rateable; FormulaLibraryRating entity + migration AddFormulaLibraryRatings
- Job Profitability report: actual labor cost (logged hours x StandardLaborRate) vs powder cost vs billed price per job; gross margin % color-coded; time-tracked-only filter; totals footer
- Quote Revision History: track Total price changes on every save; log Sent/Resent events with recipient email; replace flat table with grouped timeline UI (icons per event type, total-change badge on header)
- Setup Wizard: cap CompletedCount at TotalSteps so old 10-step data no longer shows 10/5
- Formula Library card: fix badge overflow on long titles; add Rate: label to make voting buttons discoverable
- Help docs and AI knowledge base updated for all three features

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

src/PowderCoating.Web/Controllers/FormulaLibraryController.cs

@@ -84,6 +84,31 @@ public class FormulaLibraryController : Controller
         return File(bytes, contentType ?? "image/jpeg");
     }
 
+    /// <summary>
+    /// Records or toggles a thumbs-up/down vote for the current company.
+    /// Returns updated counts so the UI can update without a page reload.
+    /// Companies cannot rate their own formulas; own-formula cards have no rating buttons.
+    /// </summary>
+    // POST: /FormulaLibrary/Rate
+    [HttpPost]
+    [ValidateAntiForgeryToken]
+    public async Task<IActionResult> Rate([FromBody] RateFormulaRequest request)
+    {
+        var companyId = _tenantContext.GetCurrentCompanyId();
+        if (companyId == null) return Json(new { success = false, message = "No company context." });
+
+        try
+        {
+            var (up, down, myVote) = await _libraryService.RateAsync(
+                request.LibraryItemId, companyId.Value, request.IsPositive);
+            return Json(new { success = true, thumbsUp = up, thumbsDown = down, myVote });
+        }
+        catch (InvalidOperationException ex)
+        {
+            return Json(new { success = false, message = ex.Message });
+        }
+    }
+
     /// <summary>Imports a library entry as a new local template for the current company.</summary>
     // POST: /FormulaLibrary/Import
     [HttpPost]
@@ -107,3 +132,11 @@ public class FormulaLibraryController : Controller
         }
     }
 }
+
+/// <summary>Body for the Rate endpoint.</summary>
+public class RateFormulaRequest
+{
+    public int LibraryItemId { get; set; }
+    /// <summary>True = thumbs up, false = thumbs down.</summary>
+    public bool IsPositive { get; set; }
+}