When a Rust-only workspace was detected, the Language-Specific Guidance
header was appearing with no content because Rust has an empty prompt
string (agent-specific prompts handle Rust instead).
The fix filters out empty prompt strings in get_language_prompts_for_workspace()
so the header only appears when there's actual guidance content.
Added test to verify Rust-only workspaces return None.
- Web Research instructions now come from skills/research/SKILL.md
- Skills are dynamically loaded and injected via generate_skills_prompt()
- Remove test_both_prompts_have_web_research test (no longer applicable)
- Remove unused G3Status::research_complete() function
This completes the externalization of research as a skill.
Replaces the built-in research/research_status tools with a portable
skill-based approach:
- Add embedded skills infrastructure (skills compiled into binary)
- Add repo-local skills/ directory support (highest priority)
- Create research skill with SKILL.md and g3-research shell script
- Script extraction to .g3/bin/ with version tracking
- Filesystem-based handoff via .g3/research/<id>/status.json
- Remove PendingResearchManager and all research tool code
- Update system prompt to reference skill instead of tool
Benefits:
- No special tool infrastructure needed (just shell + read_file)
- Context-efficient (reports stay on disk until needed)
- Crash-resilient (state persisted to filesystem)
- Portable (skill can be overridden per-workspace)
Breaking change: research tool calls now return a deprecation message
pointing to the research skill.
- Move system prompt for native tool calling models to prompts/system/native.md
- Use include_str! to embed at compile time
- Remove concatenated SHARED_* string constants
- Prompt is now readable/editable as a complete markdown document
- Non-native prompt still uses Rust constants (acceptable for now)
