feat(dgw): add Session Recording Log artifacts

[Krista House (kristahouse)]

Adds server-side support for Session Recording Log recording artifacts.

Gateway can now accept JREC recording pushes with fileType=slog, persist the raw UTF-8 NDJSON stream as .slog, and serve .slog downloads with the application/x-ndjson content type. This establishes the Gateway storage contract needed by AD Session Recording Log producers and future viewers. Consumers derive the artifact type from the file extension in recording.json.

This PR only adds the Gateway recording storage contract. Token generation remains provided by the host system, such as DVLS. Gateway standalone webapp sandbox wiring will follow separately on top of this server contract.

Issue: DGW-403

[Krista House (kristahouse)]

Implementation notes:

• Adds RecordingFileType::SessionRecordingLog with wire value slog, stored extension .slog, and application/x-ndjson pull content type.
• Extends recording.json entries with fileType, while reading older manifests by inferring missing file types from extensions.
  • Removed after review; the file type is derivable from the fileName extension, so the manifest is unchanged and consumers derive the type locally.
• Keeps Gateway write behavior as raw byte passthrough; Gateway does not parse or semantically validate SLOG NDJSON.
• Adds standalone webapp server support to issue JREC push tokens through /jet/webapp/session-token and exposes WebApp.EnableSessionRecording through config/health for the later sandbox UI PR.
  • Removed from this PR after review; standalone webapp token/config/health support belongs in the follow-up sandbox PR if needed.
• Follow-up PR will wire the Gateway standalone AD webapp toggle/package integration on top of this server contract.
• Follow-up refactor PR planned: use RecordingFileType::from_extension in streaming.rs and provide content types for the other recording file types.

Validation:

• cargo test -p devolutions-gateway --lib
• cargo check -p devolutions-gateway
• cargo clippy -p devolutions-gateway --tests -- -D warnings
• Manual smoke test against local Gateway: pushed fileType=slog, verified recording-0.slog and raw NDJSON contents.

Out of scope:

• .slog viewer/rendering.
• DVLS UI/search MVP.
• Gateway standalone webapp checkbox/package wiring.
• Media sidecar/concurrent artifact support.

[github-actions]

Let maintainers know that an action is required on their side

• Add the label release-required Please cut a new release (Devolutions Gateway, Devolutions Agent, Jetsocat, PowerShell module) when you request a maintainer to cut a new release (Devolutions Gateway, Devolutions Agent, Jetsocat, PowerShell module)

• Add the label release-blocker Follow-up is required before cutting a new release if a follow-up is required before cutting a new release

• Add the label publish-required Please publish libraries (`Devolutions.Gateway.Utils`, OpenAPI clients, etc) when you request a maintainer to publish libraries (Devolutions.Gateway.Utils, OpenAPI clients, etc.)

• Add the label publish-blocker Follow-up is required before publishing libraries if a follow-up is required before publishing libraries

[Copilot]

Pull request overview

Adds Gateway support for storing and downloading Session Recording Log (.slog) artifacts.

Changes:

• Adds the slog recording type, manifest metadata, and NDJSON responses.
• Adds standalone webapp token signing and feature configuration.
• Preserves compatibility with legacy recording manifests.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
config_schema.json	Defines the session-recording toggle.
devolutions-gateway/src/api/health.rs	Exposes the toggle in health metadata.
devolutions-gateway/src/api/jrec.rs	Serves .slog files as NDJSON.
devolutions-gateway/src/api/webapp.rs	Signs JREC push tokens.
devolutions-gateway/src/config.rs	Loads the webapp recording toggle.
devolutions-gateway/src/recording.rs	Persists artifact types and migrates manifests.
devolutions-gateway/src/token.rs	Defines the SLOG recording type.
devolutions-gateway/tests/config.rs	Updates configuration fixtures.

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[Krista House (kristahouse)]

Scope update:

• Removed the standalone webapp JREC token/config/health pieces from this PR.
• This PR now contains only the Gateway recording storage contract for fileType=slog / .slog.
• Host systems such as DVLS remain responsible for minting JREC push tokens.
• Gateway standalone webapp sandbox token/UI wiring will be handled in a separate follow-up PR.

Current changed files:

• devolutions-gateway/src/api/jrec.rs
• devolutions-gateway/src/recording.rs
• devolutions-gateway/src/token.rs

Validation after reducing scope:

• cargo test -p devolutions-gateway --lib session_recording_log
• cargo check -p devolutions-gateway
• cargo clippy -p devolutions-gateway --tests -- -D warnings

[Krista House (kristahouse)]

Post-reduction smoke test:

• Built the current PR branch release Gateway executable.
• Started an isolated local Gateway using a copied config on http://localhost:7173 / tcp://localhost:8183.
• Generated a JREC push token externally with tools/tokengen.
• Pushed UTF-8 NDJSON to /jet/jrec/push/{sessionId}?fileType=slog&token=<redacted>.
• Verified Gateway wrote recording-0.slog.
• Verified recording.json contains fileName: "recording-0.slog" and fileType: "slog".
• Verified raw NDJSON contents were preserved.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

[Benoît Cortier (CBenoit)]

Thank you!

I’m sorry, I pushed some fixup commits via the GitHub UI hoping to merge immediately, but I think there is a bigger change to make before merging. Can you look at my comments and tell me how that sounds to you? 🙏

[Benoît Cortier (CBenoit)]

LGTM!