Improve already subscribed state in frequency selector component

[benbowler]

Feature Description

Update the frequency selector component to make it clear that you are already subscribed (Figma)

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Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

• When the user is subscribed and a saved email reporting frequency exists, above frequency cards a “Current subscription” pill is shown matching the Figma design
  • The prior checkmark indicator on the card is removed.
• The selected card remains visually selected (existing selected background state stays) and the new pill replaces the checkmark as the only saved indicator.
• If the user is not subscribed or no saved frequency is present, no “Current subscription” pill is shown.

Implementation Brief

• [ ] Update assets/js/components/email-reporting/FrequencySelector.js:
  • Remove the tick/checkmark saved indicator logic.
  • Render a new badge element (e.g., div.googlesitekit-frequency-selector__current-subscription) when savedFrequency has value, placed near the top of the cards wrapper; keep existing selected styling for the card. But remove the current checkmark from individual card when saved.
• [ ] Update styles in assets/sass/components/email-reporting/_googlesitekit-frequency-selector.scss:
  • Add styling for .googlesitekit-frequency-selector__current-subscription as a small pill matching the Figma
  • Remove styles for the old .googlesitekit-frequency-selector__saved-indicator since the checkmark is gone.
• [ ] Ensure the new badge is only rendered when user is subscribed.

Test Coverage

• Update assets/js/components/email-reporting/FrequencySelector.test.js snapshots and expectations:
  • Replace saved-indicator assertions with checks for .googlesitekit-frequency-selector__current-subscription when subscribed.
  • Ensure no badge renders when not subscribed

QA Brief

Changelog entry