Split config: VRAM/model settings to config.md, agent behavior to AGENT.md

prompts/implement.md

@@ -8,6 +8,8 @@ You are in implementation mode.
 4. {project}/tasks/{task-name}/{task-name}_CONTRACT.md (if exists)
 5. {project}/tasks/{task-name}/DESIGN.md (if exists)
 6. {project}/tasks/{task-name}/TEST_PLAN.md (if exists)
+7. {project}/tasks/{task-name}/VRAM_CONFIG.md (if exists — for low-VRAM systems)
+8. {project}/tasks/{task-name}/PARENT_SPEC.md (if exists — for sub-tasks)
 
 ## Task
 
@@ -26,6 +28,18 @@ You are in implementation mode.
 - Keep functions small and focused.
 - Use existing patterns in the codebase.
 
+### VRAM-Aware Implementation (if VRAM_CONFIG.md exists)
+
+If `VRAM_CONFIG.md` is present, the implementer is working in a low-VRAM environment and must:
+
+- **Keep functions small**: Each function should be ≤ 50 lines. Break large functions into smaller ones.
+- **Avoid loading large files into context**: If implementing in an iterative environment (like pi), read files incrementally rather than loading entire files at once.
+- **Write self-contained modules**: Each module should be independently testable and runnable without loading the entire codebase.
+- **Prefer streaming over buffering**: Use streaming patterns instead of loading entire datasets into memory.
+- **Be explicit about dependencies**: Import only what you need, not the entire module.
+- **Test incrementally**: Run tests frequently rather than building up a large test suite that takes a long time to run.
+- **Optimize for low-VRAM**: Write code that can be understood and modified by an agent with limited context window.
+
 ### End State
 - You are NOT done until ALL acceptance criteria in the SPEC.md (and CONTRACT.md if it exists) are met
 - All tests must pass.