chore: release v0.56.0

[trancong12102]

A release is ready. Read the notes below as an operator would, fix a wrong line by editing the commit's PR body with a BEGIN_COMMIT_OVERRIDE block, and merge to tag and publish.

0.56.0 (2026-10-01)

Changes

• cli: accept a user name in preauthkeys create and apikeys create --user (6cb53b3)
• derp: list the embedded relay's connected clients on the debug server (6cb53b3)
• derp: read derp.paths and extra_records_path files as YAML, JSON or HuJSON by extension (6cb53b3)

Fixes

• derp: drop a region set to null in a derp.paths file (6cb53b3)
• mapper: send a removed peer in a response clients apply as a delta (6cb53b3)
• nix: write split DNS where slopscale reads it and drop the deprecated ephemeral key (6cb53b3)
• policy/v2: keep via exit steering when an unrelated rule matches the viewer (6cb53b3)
• policy/v2: leave the live policy in place when a recompile fails (6cb53b3)
• policy/v2: send machines their new autogroup:self rules when a user changes (6cb53b3)
• policy: send approved exit nodes every filter rule, as Tailscale does (6cb53b3)
• state: send a deleted node's removal on its own, apart from the policy refresh (6cb53b3)
• state: update a node's NextDNS device name when its hostname changes (6cb53b3)
• types: refuse a relay host name that clients behind a proxy would reject (6cb53b3)

Performance

• state: build the peer map once per node write instead of twice (6cb53b3)

Dependencies

• update tailscale main, zitadel/oidc, maxminddb, the console and docs pins and nixpkgs (6cb53b3)

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[trancong12102]

🤖 Created releases:

• v0.56.0

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