FN-5791: add markdown goal descriptions with show-more toggle

Improve goal card descriptions to support markdown formatting while keeping long content scannable.

- render goal descriptions with markdown + GFM support in GoalsView
- collapse long or multi-line descriptions by default and add Show more/Show less disclosure
- style collapsed description layout and add responsive clamp adjustments
- add tests for markdown rendering, long-description toggle behavior, and short-description no-toggle behavior

Files changed:
 packages/dashboard/app/components/GoalsView.css    | 27 +++++++++++++
 packages/dashboard/app/components/GoalsView.tsx    | 46 +++++++++++++++++++++-
 packages/dashboard/app/components/__tests__/GoalsView.test.tsx    | 42 ++++++++++++++++++++
 3 files changed, 114 insertions(+), 1 deletion(-)

Fusion-Task-Id: FN-5791

Fusion-Task-Lineage: a3a0be5c-4a8d-4dc1-93a3-40891ab7762b

packages/dashboard/app/components/GoalsView.css

@@ -112,6 +112,28 @@
   color: var(--text-muted);
 }
 
+.goals-card-description > :first-child {
+  margin-top: 0;
+}
+
+.goals-card-description > :last-child {
+  margin-bottom: 0;
+}
+
+.goals-card-description-collapsed {
+  display: -webkit-box;
+  -webkit-box-orient: vertical;
+  -webkit-line-clamp: 4;
+  overflow: hidden;
+  max-height: calc(var(--space-md) * 6);
+}
+
+.goals-card-description-toggle {
+  margin-top: var(--space-xs);
+  align-self: flex-start;
+  color: var(--text-muted);
+}
+
 .goals-card-status {
   margin: var(--space-xs) 0 0;
   color: var(--text-muted);
@@ -145,4 +167,9 @@
   .goals-card-actions {
     flex-direction: column;
   }
+
+  .goals-card-description-collapsed {
+    -webkit-line-clamp: 3;
+    max-height: calc(var(--space-md) * 5);
+  }
 }