Fix README with no extension not appearing in Workspace Wiki

[AlexJSully]

No description provided.

[Copilot]

Pull Request Overview

This PR adds support for README files without extensions to be recognized and treated as Markdown files in the Workspace Wiki extension. The fix ensures that extension-less README files appear in the workspace tree and use the appropriate preview mode.

• Extends the workspace scanner to include README files (no extension) when Markdown is supported
• Updates the tree provider to handle preview commands for extension-less README files
• Adds comprehensive test coverage for the new functionality

Reviewed Changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/scanner/workspaceScanner.ts	Adds scanning patterns for extension-less README files when Markdown is supported
src/tree/treeProvider.ts	Implements special handling for README files without extensions in preview mode
src/scanner/workspaceScanner.test.ts	Adds unit tests for README scanning with and without Markdown support
src/tree/treeProvider.test.ts	Adds comprehensive test coverage for README preview command handling
docs/architecture/scanner.md	Updates documentation to reflect README scanning support
docs/architecture/settings.md	Documents the special case for README files
README.md	Updates the main README to explain README file support
package.json	Version bump to 1.0.4
example/nested-structure-test/subdirectory-3/README	Adds test README file
example/file-types-test/test-proto.proto	Adds test proto file