feat: Add hierarchical .roo configuration resolution for mono-repos

[roomote]

Description

This PR implements hierarchical configuration resolution for .roo directories and .roomodes files in mono-repositories, addressing Issue #8825.

Problem

In mono-repository setups, the current .roo resolution only checks global (~/.roo) and workspace-local directories. This makes it challenging to manage configurations for projects with multiple tech stacks and nested workspace structures.

Solution

This implementation introduces hierarchical directory walking, similar to .editorconfig and nuget.config behavior. The configuration system now:

1. Walks up the directory tree from the current workspace
2. Collects all .roo directories and .roomodes files in the hierarchy
3. Merges configurations with more specific settings overriding general ones
4. Maintains backward compatibility with a legacy mode flag

Changes

Core Implementation

• Enhanced getRooDirectoriesForCwd() in src/services/roo-config/index.ts to support hierarchical resolution
• Updated CustomModesManager to handle multiple .roomodes files in the hierarchy
• Added getHierarchicalRoomodes() method for discovering .roomodes files up the directory tree

Key Features

• ✅ Hierarchical directory traversal from workspace to parent directories
• ✅ Protection against infinite loops and circular references
• ✅ Platform-specific path handling (Windows/Unix)
• ✅ Respects home directory boundaries
• ✅ Backward compatibility via optional enableHierarchical parameter (defaults to true)

Testing

• Added comprehensive test suite in src/services/roo-config/__tests__/hierarchical-resolution.spec.ts
• Updated existing tests to maintain backward compatibility
• All tests passing ✅

Example

For a project structure:

/home/user/
├── .roo/                         # Global config
├── mono-repo/
│   ├── .roo/                     # Repository-wide config
│   └── packages/
│       ├── .roo/                 # Packages-specific config
│       └── frontend/
│           └── .roo/             # Frontend-specific config

The resolution order is now:

1. /home/user/.roo (global - least specific)
2. /home/user/mono-repo/.roo
3. /home/user/mono-repo/packages/.roo
4. /home/user/mono-repo/packages/frontend/.roo (most specific)

Breaking Changes

None - the feature is enabled by default but maintains full backward compatibility.

Testing Instructions

1. Create a nested directory structure with .roo folders at different levels
2. Add different configurations at each level
3. Verify that more specific configurations override general ones
4. Test with enableHierarchical: false to verify legacy behavior

Fixes #8825

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Important

Adds hierarchical resolution for .roo directories and .roomodes files, allowing configurations to be resolved from global to specific in mono-repos, with backward compatibility.

• Behavior:
  • Implements hierarchical resolution for .roo directories and .roomodes files in CustomModesManager and getRooDirectoriesForCwd().
  • Configurations are merged from global to specific, with specific settings overriding general ones.
  • Backward compatibility maintained with enableHierarchical flag (default true).
• Core Implementation:
  • getHierarchicalRoomodes() in CustomModesManager collects .roomodes files up the directory tree.
  • getRooDirectoriesForCwd() in index.ts resolves directories hierarchically.
• Testing:
  • Added hierarchical-resolution.spec.ts for comprehensive testing of hierarchical resolution.
  • Updated existing tests in index.spec.ts to ensure backward compatibility.

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Review Summary

I've reviewed this PR and identified 1 issue that should be addressed:

• File watcher doesn't monitor parent directory .roomodes files - changes to .roomodes files outside the workspace won't trigger updates

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Follow Along on Roo Code Cloud

[roomote]

The file watcher pattern **/.roomodes only watches files within the workspace directory, but getHierarchicalRoomodes() walks up to parent directories outside the workspace. This means changes to .roomodes files in parent directories won't trigger updates, requiring users to restart VSCode. For example, if the workspace is /home/user/mono-repo/packages/frontend and there's a .roomodes at /home/user/mono-repo/.roomodes, changes to the parent file won't be detected since it's outside the workspace tree being watched.