sse

• Update the minimum Dart SDK version to 3.11.0.
• Handle out of order disconnects and reconnects.
  • Allow SSE connections to be reused if not in a keep alive period.
  • Allow a debounce period after connections to ignore disconnects which may be from prior connections.
  • Add logging when messages are received out of order.

• Simplify the format of client ID strings.

• Move to dart-lang/tools monorepo.

• Require package web: '>=0.5.0 <2.0.0'.

• Drop unneeded dependency on package:js.
• Update the minimum Dart SDK version to 3.3.0.
• Support the latest package:web.

• Fix incorrect cast causing failure with dart2wasm.

• Update the minimum Dart SDK version to 3.2.0.

• Send fetch requests instead of XHR requests.
• Add an optional debugKey parameter to SseClient to include in logging.
• Add a dependency on package:js.
• Update the minimum Dart SDK version to 2.16.0.

• Apply keepAlive logic to SocketExceptions.
• Switch from using package:pedantic to package:lints
• Rev the minimum required SDK to 2.15.
• Populate the pubspec repository field.

• Limit the number of concurrent requests to prevent Chrome from automatically dropping them on the floor.

• Support null safety.

• Require the latest shelf and remove dead code.

• Fix an issue where closing the SseConnection stream would result in an error.

• Add onConnected to replace onOpen.
• Fix an issue where failed requests would not add a done event to the connection sink.

• Deprecate the client's onOpen getter. Messages will now be buffered until a connection is established.

• Drop dependency on package:uuid.

• Improve performance by buffering out of order messages in the server instead of the client.

** Note ** This is not modelled as a breaking change as the server can handle messages from older clients. However, clients should be using the latest server if they require order guarantees.

• Add new shutdown methods on SseHandler and SseConnection to allow closing connections immediately, ignoring any keep-alive periods.

• Remove onClose from SseConnection and ensure the corresponding sink.close correctly fires.

• Add an onClose event to the SseConnection. This allows consumers to listen to this event in lue of sseConnection.sink.done as that is not guaranteed to fire.

• Fix an issue where keepAlive may cause state errors when attempting to send messages on a closed stream.

• Fix an issue where keepAlive would only allow a single reconnection.

• Re-expose isInKeepAlivePeriod flag on SseConnection. This flag will be true when a connection has been dropped and is in the keep-alive period waiting for a client to reconnect.

• Fix an issue where the SseClient would not send a done event when there was an error with the SSE connection.

• Make isInKeepAlive on SseConnection private.

Note that this is a breaking change but in actuality no one should be depending on this API.

• Add optional keepAlive parameter to the SseHandler. If keepAlive is supplied, the connection will remain active for this period after a disconnect and can be reconnected transparently. If there is no reconnect within that period, the connection will be closed normally.

• Adds discovery API to find both a configuration and its location:
  findPackageConfigAndFile and findPackageConfigAndUri.
• Removes support for the .packages file.
  The Dart SDK no longer supports that file, and no new .packages files
  will be generated.
  Since the SDK requirement for this package is above 3.0.0,
  no supporting SDK can use or generate .packages.
• Simplifies API that no longer needs to support two separate files.
  • Renamed readAnyConfigFile to readConfigFile, and removed
    the preferNewest parameter.
  • Same for readAnyConfigFileUri which becomes readConfigFileUri.
  • Old functions still exists as deprecated, forwarding to the new
    functions without the preferNewest argument.
    Makes PackageConfig, Package and LanguageVersion @sealed classes,
    in preparation for making them final in a future update.
• Adds PackageConfig.minVersion to complement .maxVersion.
  Currently both are 2.

• Add retry logic.

Possible Breaking Change Error messages may now be delayed up to 5 seconds in the client.

• Remove package:http dependency.

• Use proper headers delimiter.

• Support Firefox.

• Fix an issue where messages could come out of order.

• Support the latest package:stream_channel.
• Require Dart SDK >=2.1.0 <3.0.0.

• Update to package:uuid version 2.0.

• No longer expose close and onClose on an SseConnection. This is simply handled by the underlying stream / sink.
• Fix a bug where resources of the SseConnection were not properly closed.

• Internal cleanup.

• Initial commit.