[ENHANCEMENT] Revamp codebase index

[RepairYourTech]

Problem (one or two sentences)

current codebase index uses basic vectors and lacks any true indexing capabilities for codebases

Context (who is affected and when)

every user who wants to vibe code especially on brownfield projects or greenfields that are expected to grow large

Desired behavior (conceptual, not technical)

roo will have unmatched understanding of users codebase

Constraints / preferences (optional)

No response

Request checklist

• I've searched existing Issues and Discussions for duplicates
• This describes a specific problem with clear context and impact

Roo Code Task Links (optional)

No response

Acceptance criteria (optional)

No response

Proposed approach (optional)

No response

Trade-offs / risks (optional)

No response

[roomote]

I'm exploring a potential fix for the codebase indexing enhancement and will open a PR to share progress.

[roomote]

Opened a PR with my attempt at addressing this issue: #9405

The implementation introduces graph-based indexing alongside the existing vector store to enable hierarchical code understanding. Key improvements include:

• Graph-based relationships between code elements
• Semantic chunking that respects code structure
• Context-aware search with relationship traversal
• Support for multiple programming languages

Feedback welcome!