refactor(storage): drop the unreachable cap-only lifecycle branch

Follows the same change in the version-fate helper: a version cap always arrives
alongside an expiration age, so the policy summary only has three shapes to
describe (age alone, or age plus cap under either operator). Removes the
cap-only sentence and the "no age limit" chip, and `daysRemaining` on
`expires-on-next-upload` no longer needs an undefined guard.

Also adds the explicit `tabIndex={0}` that `supabase/require-explicit-tabindex`
wants on the four raw buttons in this feature. These were lint *errors*, not
warnings, so the ratchet never surfaced them.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

apps/studio/components/interfaces/Storage/StorageExplorer/PreviewSection.tsx

@@ -23,6 +23,7 @@ export const PreviewSection = ({
       <CollapsibleTrigger asChild>
         <button
           type="button"
+          tabIndex={0}
           className="flex w-full items-center justify-between py-3 text-left text-sm font-medium text-foreground transition-colors hover:text-foreground-light"
         >
           <span className="flex items-center gap-x-2">

apps/studio/components/interfaces/Storage/StorageExplorer/VersionCompareWidget.tsx

@@ -35,6 +35,7 @@ export const VersionCompareWidget = ({
       </p>
       <button
         type="button"
+        tabIndex={0}
         className="ml-auto shrink-0 text-foreground-lighter transition-colors hover:text-foreground"
         onClick={onDismiss}
         aria-label="Cancel comparison"

apps/studio/components/interfaces/Storage/StorageExplorer/VersionHistory.tsx

@@ -52,9 +52,7 @@ const VersionFateLabel = ({ fate }: { fate: VersionFate }) => {
       return (
         <div className="flex flex-col items-end">
           <span className="shrink-0 text-xs text-warning-600">Expires on next upload</span>
-          {fate.daysRemaining !== undefined && (
-            <span className="shrink-0 text-xs text-warning-600">or in {fate.daysRemaining}d</span>
-          )}
+          <span className="shrink-0 text-xs text-warning-600">or in {fate.daysRemaining}d</span>
         </div>
       )
     case 'expiring-now':
@@ -288,6 +286,7 @@ export const VersionHistory = ({
                 ) : (
                   <button
                     type="button"
+                    tabIndex={0}
                     className="flex min-w-0 flex-1 items-center gap-x-2.5 text-left"
                     onClick={() => (version.isCurrent ? clearPreview() : onPreview?.(version))}
                   >

apps/studio/components/interfaces/Storage/StorageExplorer/VersionHistoryPolicyRow.tsx

@@ -34,34 +34,27 @@ interface PolicyRuleProps {
 
 /** The policy spelled out in plain language, for the hover card. */
 const PolicyFullRule = ({ cap, expiryDays, mode }: PolicyRuleProps) => {
+  // A cap always arrives with an age, so there are only three shapes to describe:
+  // age alone, or age combined with the cap under either operator.
   const hasCap = cap !== null && cap > 0
-  const hasExpiryDays = expiryDays !== null && expiryDays > 0
 
-  if (hasCap && hasExpiryDays) {
-    if (mode === 'and') {
-      return (
-        <>
-          A noncurrent version is permanently deleted only once it is <em>both</em> older than{' '}
-          {expiryDays} days and beyond the {cap} newest noncurrent versions.
-        </>
-      )
-    }
+  if (!hasCap) {
+    return <>A noncurrent version is permanently deleted once it is older than {expiryDays} days.</>
+  }
+
+  if (mode === 'and') {
     return (
       <>
-        A noncurrent version is permanently deleted as soon as it is <em>either</em> older than{' '}
-        {expiryDays} days <em>or</em> beyond the {cap} newest noncurrent versions.
+        A noncurrent version is permanently deleted only once it is <em>both</em> older than{' '}
+        {expiryDays} days and beyond the {cap} newest noncurrent versions.
       </>
     )
   }
 
-  if (hasExpiryDays) {
-    return <>A noncurrent version is permanently deleted once it is older than {expiryDays} days.</>
-  }
-
   return (
     <>
-      Only the {cap} newest noncurrent versions are retained. Older ones are deleted on the next
-      upload.
+      A noncurrent version is permanently deleted as soon as it is <em>either</em> older than{' '}
+      {expiryDays} days <em>or</em> beyond the {cap} newest noncurrent versions.
     </>
   )
 }
@@ -91,6 +84,7 @@ export const VersionHistoryPolicyRow = ({
       <HoverCardTrigger asChild>
         <button
           type="button"
+          tabIndex={0}
           onClick={onEditBucket}
           className="flex items-center gap-x-2 text-left"
           aria-label="Lifecycle policy details"
@@ -106,9 +100,6 @@ export const VersionHistoryPolicyRow = ({
               — no retention cap
             </span>
           )}
-          {hasCap && !hasExpiryDays && (
-            <span className="font-mono text-[11px] text-foreground-lighter">— no age limit</span>
-          )}
           <Info size={13} className="text-foreground-lighter" />
         </button>
       </HoverCardTrigger>