docs: v0.102.0 REPORT + CONTEXT — async restore family, F4 UX fixed + live-validated

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PSK5g6qYLknKj8u3QAFEr6

CONTEXT.md

@@ -7,7 +7,17 @@
 >
 > Ask Claude Code: "Please update CONTEXT.md with what we did today"
 
-Last updated: 2026-07-06 (v0.101.0 — no-mercy campaign findings F3 + F2-surfacing)
+Last updated: 2026-07-06 (v0.102.0 — async restore family; F4 re-adjudicated + fixed)
+
+> **2026-07-06 — v0.102.0: async restore family (F4 UX fix, LIVE on 9201).** All three restore surfaces
+> (`/backup/restore`, `/backup/tier2/restore`, `/backup/offbox/restore`) blocked the HTTP request until
+> completion → through cloudflared's 100s cap a customer got an error page while the restore succeeded
+> (offbox worse: bounded on `r.Context()`, canceling the SFTP restore mid-flight). Now async (offboxRun
+> shape): fast-path IsRunning refuse → background goroutine (offbox ctx off r.Context()→Background+30m) →
+> instant redirect. New `GET /api/backup/restore-status` + mutex op-status (`opstatus.go`) + 3s-polling
+> `backups.html` banner. Live-proven: restore POST 0.018s internal / **0.235s external (F4 tunnel)**, canary
+> bit-identical, status transitions. Restore single-flight unchanged. OPEN: op-status is in-memory (no
+> persistence, by design).
 
 > **2026-07-06 — v0.101.0: no-mercy campaign findings.** F3: git subprocess deadline in
 > `internal/sync/sync.go` (`gitCmdTimeout=120s`, `exec.CommandContext`) — a hung remote no longer