feat(savings_goals): drop Accounts section from index

The Accounts grid duplicated the sidebar account list. Removing it gives
the Goals section more breathing room and the page a tighter narrative:
header → KPIs → Goals.

Delete Savings::AccountCardComponent, Family#savings_subtype_accounts,
the @savings_accounts / @account_goal_counts controller refs, and the
related locale keys. Sidebar still shows the savings-subtype Depository
accounts under "Cash" — no information is lost.

app/components/savings/account_card_component.html.erb

@@ -1,16 +0,0 @@
-<div class="bg-container rounded-xl shadow-border-xs p-6">
-  <div class="flex items-center gap-3 mb-3">
-    <span class="inline-flex items-center justify-center w-9 h-9 rounded-full text-inverse text-sm font-semibold"
-          style="background-color: var(--color-blue-500);">
-      <%= initial %>
-    </span>
-    <div class="min-w-0 flex-1">
-      <p class="text-sm font-medium text-primary truncate"><%= account.name %></p>
-      <p class="text-xs text-secondary"><%= subtype_label %></p>
-    </div>
-  </div>
-  <p class="text-2xl font-medium text-primary tabular-nums privacy-sensitive">
-    <%= Money.new(account.balance, account.currency).format %>
-  </p>
-  <p class="text-xs text-subdued mt-1"><%= funds_label %></p>
-</div>

app/components/savings/account_card_component.rb

@@ -1,20 +0,0 @@
-class Savings::AccountCardComponent < ApplicationComponent
-  def initialize(account:, goals_count: 0)
-    @account = account
-    @goals_count = goals_count
-  end
-
-  attr_reader :account, :goals_count
-
-  def initial
-    account.name.to_s.strip.first&.upcase || "?"
-  end
-
-  def subtype_label
-    (account.subtype || "savings").to_s.titleize
-  end
-
-  def funds_label
-    I18n.t("savings_goals.index.account_card.funds", count: goals_count)
-  end
-end