Add settings page and proxy configuration

[ActiveChooN]

Added settings page to the application:

Added proxy support to the application with following algorithm:

• The getProxy() function attempts to fetch the proxy configuration from a WPAD (Web Proxy Auto-Discovery) server.
• If the WPAD server is not available, it falls back to checking environment variables for proxy settings.
• If no env variables, do not use proxy

[github-actions]

license-eye has checked 450 files.

Valid	Invalid	Ignored	Fixed
190	1	259	0

Click to see the invalid file list

• lib/pages/settings/settings.dart

Use this command to fix any missing license headers

```bash

docker run -it --rm -v $(pwd):/github/workspace apache/skywalking-eyes header fix

</details>

[github-actions]

Suggested change

	// Copyright 2025 Intel Corporation.
	// Copyright (c) 2024 Intel Corporation
	//
	// SPDX-License-Identifier: Apache-2.0
	// Copyright 2025 Intel Corporation.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 62 lines in your changes missing coverage. Please review.

Project coverage is 32.33%. Comparing base (59919f5) to head (6ad7dfc).

Files with missing lines	Patch %	Lines
lib/config.dart	0.00%	30 Missing ⚠️
lib/utils.dart	0.00%	28 Missing ⚠️
lib/theme_fluent.dart	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #85      +/-   ##
==========================================
- Coverage   33.33%   32.33%   -1.00%     
==========================================
  Files          39       39              
  Lines        1494     1540      +46     
==========================================
  Hits          498      498              
- Misses        996     1042      +46     

Flag	Coverage Δ
unittests	32.33% <0.00%> (-1.00%)	⬇️

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