fix: clarify folded file context blocks during condensation

[roomote-v0]

Related GitHub Issue

Closes: #11989

Description

This PR attempts to address Issue #11989 where models misinterpret condensed file summaries as "compressed" read_file output, causing them to repeatedly fetch small snippets instead of reading full files.

The fix adds a brief explanatory note to each <system-reminder> block generated during context condensation:

(Structural summary from context condensation - shows signatures only. Use read_file to get full content when needed.)

This note appears between the ## File Context: header and the tree-sitter definitions, making it clear to the model that:

• This is a structural summary (signatures only), not compressed file content
• It was generated during context condensation, not by the read_file tool
• The model should use read_file to get full content when implementation details are needed

Files changed:

• src/core/condense/foldedFileContext.ts - Added explanatory note to both normal and truncated section templates
• src/core/condense/__tests__/foldedFileContext.spec.ts - Added test verifying the explanatory note is present and correctly positioned; adjusted budget test threshold

Test Procedure

• All 123 existing condense tests pass (cd src && npx vitest run core/condense/__tests__/)
• New test verifies the explanatory note appears between the header and definitions
• Linting and type checks pass across all packages

Pre-Submission Checklist

• Issue Linked: This PR is linked to an approved GitHub Issue.
• Scope: Changes are focused on the linked issue.
• Self-Review: I have performed a thorough self-review of my code.
• Testing: New test added to cover the explanatory note.
• Documentation Impact: No documentation updates required.
• Contribution Guidelines: I have read and agree to the Contributor Guidelines.

Documentation Updates

• No documentation updates are required.

Additional Notes

Feedback and guidance are welcome.

Interactively review PR in Roo Code Cloud