Allow characteristic setters to get the username of the triggering connection

[ccutrer]

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[Copilot]

Pull Request Overview

This PR adds the ability for characteristic setters to receive the username of the triggering connection, enabling developers to track which authenticated user made changes to device characteristics.

Key Changes:

• Extended the characteristic setter chain to include an optional username parameter throughout the API
• Modified the pairing verification flow to capture and propagate the authenticated username through the connection lifecycle
• Added backward-compatible default implementations to maintain existing API compatibility

Reviewed Changes

Copilot reviewed 14 out of 15 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
UpgradeResponse.java	Added username field to store authenticated user identity during connection upgrade
PairVerifyManager.java	Extracted username string to pass to UpgradeResponse and reuse in logging
CharacteristicsController.java	Updated characteristic setValue call to include connection username
HomekitClientConnection.java	Added getUsername() method to interface with default null implementation
ConnectionImpl.java	Implemented username storage and getter from upgrade response
HomekitServer.java	Applied code formatting to method call
StringCharacteristic.java	Added setValue overload accepting username parameter
IntegerCharacteristic.java	Added setValue overload accepting username parameter
FloatCharacteristic.java	Added setValue overload accepting username parameter
EnumCharacteristic.java	Added setValue overloads accepting username parameter for both generic and Integer types
BooleanCharacteristic.java	Added setValue overload accepting username parameter
BaseCharacteristic.java	Added setValue overload and default implementation with username parameter
ExceptionalConsumer.java	Added default accept method overload with username parameter
Characteristic.java	Added setValue interface method with username parameter

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[yfre]

LGTM
thank you @ccutrer !