Syncher 0.3.0

Renamed from Obsyncher to Syncher (plugin id syncher): the Obsidian directory rejects plugin names that contain
parts of "Obsidian". The repository moved to github.com/tequrity/syncher.

Changed

• New name everywhere: plugin id and name, UI texts, the server metadata folder (.syncher), the relay
  (server/syncher-relay.py, service syncher-relay), the config file (syncher.config.json), dist/syncher.
• SSH keys are no longer read from files on disk. The key is imported once in the settings
  (Import key… — file picker or pasted text) and stored encrypted. The "Key file" setting and the keysDir/keyFile
  config entries are gone, so the plugin never reads files outside the vault.
• The default device name no longer uses the computer's name (Desktop-xxxx / Android-xxxx instead); the plugin
  reads no system identity information.

Added

• Automatic migration from Obsyncher: on its first start Syncher takes over the old plugin's settings, sync base,
  sync_ignore and config, keeps the device identity and the encrypted secrets (old master key id and HKDF label are
  still accepted), disables the old plugin, and renames the server's .obsyncher folder to .syncher.
  install-relay.sh removes a relay installed under the old name.
• Signed build provenance (GitHub artifact attestations) for the release assets.