feat(dgw): let a recorder push its session events log

[irvingouj@Devolutions (irvingoujAtDevolution)]

A recorder can now push a session events log (.slog) next to its recording, on the existing push route, with a push token of its own (same jet_aid, its own jti):

/jet/jrec/push/{id}?fileType=slog&artifact=events

The log goes under artifacts.events in recording.json, not in files. So clips, the shadow stream, the recording policy and remux don't change. Without artifact, a push works like today.

• A reconnecting recorder appends to the same events-0.slog, while its token can still be reused: same source IP, and the recording push still active or in its reconnect window.
• A second events push at the same time is refused, like a second clip push.
• The events push never touches the recording: it doesn't keep the session active, so token reuse, the reconnect window, the delete conflict and the ?active=true listing work exactly like today.
• The events push has its own token, so it never touches the recording token's replay check. The issuer (DVLS) mints both.
• An events push before the recording is refused, and creates no session folder or manifest: those belong to the recording.

The AI analysis (#2044) only reads the locale of this log; it writes its own ai-analysis-0.slog.

Where to look hardest: handle_connect_events / handle_disconnect_events in recording.rs, and that nothing else of the recording reads events_pushes.

Tests: unit tests in recording.rs for each case above.

🤖 Generated with Claude Code

[Copilot]

🟡 Changes recommended

Token-reuse handling can reject events reconnections and concurrent clip/events startup.

2 open issues

• Register pending pushes before allowing token reuse · New
• Preserve token reuse through the events reconnect window · New

What changed in this PR

Adds recorder-uploaded session events logs alongside recording clips, preparing for later AI enrichment.

Changes:

• Routes artifact=events pushes to an append-only .slog artifact.
• Tracks events connections separately from clips.
• Adds lifecycle and manifest tests.

File	Description
devolutions-gateway/​src/​recording.rs	Adds events-push lifecycle, append behavior, and tests.
devolutions-gateway/​src/​artifacts.rs	Adds events artifact storage and enumeration.
devolutions-gateway/​src/​api/​jrec.rs	Validates and routes events push requests.

_{Review effort: Balanced}