perf: bound DM subsystem network concurrency

Replaces unbounded Promise.all with pMap and RELAY_BACKGROUND_CONCURRENCY (3) in js/nostr/dmSignalEvents.js and js/services/dmNostrService.js to prevent network saturation. Includes context logs and daily performance report.

Co-authored-by: PR0M3TH3AN <[email protected]>

docs/agents/task-logs/daily/2026-02-17_07-39-33_perf-agent_completed.md

@@ -0,0 +1,22 @@
+# perf-agent Daily Run - 2026-02-17
+
+## Status: Completed
+
+**Goals:**
+- Identify and fix unbounded concurrency in network operations.
+- Audit upload documentation.
+
+**Actions:**
+- **Identified:** Unbounded `Promise.all` usage in `js/nostr/dmSignalEvents.js` and `js/services/dmNostrService.js`.
+- **Fixed:** Replaced with `pMap` and `RELAY_BACKGROUND_CONCURRENCY` (3).
+- **Verified:** Documentation in `content/docs/guides/upload-content.md` correctly specifies port 3000.
+- **Tested:** Unit and integration tests for DM subsystem passed.
+
+**Files Changed:**
+- `js/nostr/dmSignalEvents.js`
+- `js/services/dmNostrService.js`
+- `daily-perf-report-2026-02-17.md`
+- Context/Logs: `context/`, `todo/`, `decisions/`, `test_logs/`
+
+**Metrics:**
+- DM network concurrency bounded to 3 (was unbounded).