feat: add Codex session management and automatic restoration

src/services/codexSessionState.ts

@@ -0,0 +1,89 @@
+export type CodexSessionSummary = {
+  id: string;
+  title: string;
+  cwd: string;
+  modelProvider: string;
+  archived: boolean;
+  updatedAtMs: number | null;
+  databasePath: string;
+};
+
+export type CodexSessionPage = {
+  codexHome: string;
+  databasePaths: string[];
+  sessions: CodexSessionSummary[];
+  offset: number;
+  limit: number;
+  hasMore: boolean;
+  repairOnLaunch: boolean;
+  warnings: string[];
+};
+
+export type CodexSessionDeleteResult = {
+  sessionId: string;
+  status: 'deleted' | 'partial' | 'notFound' | 'failed';
+  message: string;
+  backupPath: string | null;
+};
+
+export type CodexSessionDeleteBatchResult = {
+  results: CodexSessionDeleteResult[];
+  deletedCount: number;
+  failedCount: number;
+};
+
+export type CodexSessionRepairProgress = {
+  phase: 'scanning' | 'backingUp' | 'rewriting' | 'updatingDatabase' | 'complete';
+  percent: number;
+  processed: number;
+  total: number;
+};
+
+export type CodexSessionRepairResult = {
+  targetProvider: string;
+  changedRolloutFiles: number;
+  sqliteRowsUpdated: number;
+  skippedLockedFiles: string[];
+  backupPath: string | null;
+  encryptedContentWarning: string | null;
+  warnings: string[];
+};
+
+export type SessionIndexCleanupCandidate = {
+  id: string;
+  threadName: string;
+  updatedAt: string;
+};
+
+export type SessionIndexCleanupPreview = {
+  snapshotSha256: string;
+  candidates: SessionIndexCleanupCandidate[];
+};
+
+export type SessionIndexCleanupResult = {
+  prunedEntries: number;
+  backupPath: string | null;
+};
+
+export type CodexSessionPageCounts = {
+  active: number;
+  archived: number;
+};
+
+export function codexSessionPageCounts(
+  sessions: readonly Pick<CodexSessionSummary, 'archived'>[],
+): CodexSessionPageCounts {
+  const archived = sessions.reduce(
+    (count, session) => count + Number(session.archived),
+    0,
+  );
+  return { active: sessions.length - archived, archived };
+}
+
+export function retainVisibleCodexSessionIds(
+  selectedIds: ReadonlySet<string>,
+  sessions: readonly Pick<CodexSessionSummary, 'id'>[],
+): Set<string> {
+  const visibleIds = new Set(sessions.map((session) => session.id));
+  return new Set(Array.from(selectedIds).filter((id) => visibleIds.has(id)));
+}