Change removed functions color

Use purple (with gradients) for both removed and new functions to
unify these “out-of-band” cases under a single visual language,
meaning no direct comparison is available. This keeps them clearly
separate from the red/blue performance axis and simplifies the
legend: “purple = this function has no counterpart in the other
profile.”

Author: ivonastojanovic

Lib/profiling/sampling/_flamegraph_assets/flamegraph.css

@@ -25,7 +25,7 @@
   /* Other differential colors */
   --diff-neutral: #bdbdbd;
   --diff-new: #9575cd;
-  --diff-elided: #d32f2f;
+  --diff-elided: #b39ddb;
 }
 
 /* --------------------------------------------------------------------------

Lib/profiling/sampling/_flamegraph_assets/flamegraph_template.html

@@ -407,13 +407,13 @@ <h3 class="section-title">Differential Colors</h3>
                 </div>
                 <div class="legend-item">
                   <div class="legend-color" style="background: var(--diff-new)"></div>
-                  <span class="legend-label">New Function</span>
-                  <span class="legend-range">Not in baseline</span>
+                  <span class="legend-label">New</span>
+                  <span class="legend-range">No counterpart in baseline</span>
                 </div>
                 <div class="legend-item">
                   <div class="legend-color" style="background: var(--diff-elided)"></div>
-                  <span class="legend-label">Elided (Removed)</span>
-                  <span class="legend-range">Not in current</span>
+                  <span class="legend-label">Removed</span>
+                  <span class="legend-range">No counterpart in current</span>
                 </div>
               </div>
               </div>