feat(voice): add async selectable summaries

tests/voice-state.test.js

@@ -22,6 +22,7 @@ function session(overrides = {}) {
     failedSegmentCount: 0,
     needsGeneration: false,
     lessons: [],
+    latestSummaryRun: null,
     createdAt: 0,
     updatedAt: 0,
     ...overrides
@@ -40,10 +41,10 @@ test('failed segments take priority over processing and generation', () => {
   assert.equal(getVoicePrimaryActionText(action, value.failedSegmentCount), '重试转录（2）')
 })
 
-test('voice primary action follows retry, processing, then generation states', () => {
+test('voice primary action keeps summary generation separate from save', () => {
   assert.equal(getVoicePrimaryAction(session({ failedSegmentCount: 1 })), 'retry')
   assert.equal(getVoicePrimaryAction(session({ processingSegmentCount: 1 })), 'processing')
-  assert.equal(getVoicePrimaryAction(session({ needsGeneration: true })), 'generate')
+  assert.equal(getVoicePrimaryAction(session({ needsGeneration: true })), 'save')
 })
 
 test('no clear speech failures provide an actionable explanation', () => {