M10: ProcessingRunner skeleton

- Add modules/runtime/runner.py with ProcessingRunner and ProcessingRequest
- Wire process_images to delegate through runner (internal only)
- Add test/quality/test_processing_runner.py contract test

Behavior-preserving. Zero blast radius. All callers unchanged.

Made-with: Cursor

docs/milestones/M10/M10_plan.md

@@ -0,0 +1,125 @@
+# M10 — ProcessingRunner Skeleton
+
+Phase: **Phase III — Runner & Service Boundary**
+Status: Planned
+
+---
+
+# 1. Intent / Target
+
+Introduce the **ProcessingRunner** abstraction that will become the unified execution surface for Serena.
+
+Currently the pipeline is invoked directly through internal orchestration code.
+This milestone introduces a **runner boundary** that:
+
+- encapsulates pipeline execution
+- standardizes runtime entrypoints
+- prepares Serena for CLI / API / service mode
+
+The runner initially acts as a **thin adapter** around existing behavior.
+
+No behavior changes are permitted.
+
+---
+
+# 2. Scope Boundaries
+
+### In scope
+
+- Create `ProcessingRunner` skeleton at `modules/runtime/runner.py`
+- Define `ProcessingRequest` wrapping `StableDiffusionProcessing`
+- Wire `process_images` to delegate through runner (internal only)
+- Maintain existing CLI/UI/API/scripts behavior
+- Add minimal contract test at `test/quality/test_processing_runner.py`
+
+### Out of scope
+
+- No runtime behavior changes
+- No async processing yet
+- No service layer
+- No multiprocessing
+- No new configuration surfaces
+- No performance changes
+- No RuntimeContext in runner (M10)
+
+---
+
+# 3. Clarifications (Authoritative)
+
+| Decision | Choice |
+|----------|--------|
+| Module path | `modules/runtime/runner.py` |
+| ProcessingRequest | Wraps `p`: `ProcessingRequest(processing=p)` |
+| RuntimeContext | Not passed to runner; omit from constructor |
+| Wiring | Inside `process_images` only; all callers unchanged |
+| Test location | `test/quality/test_processing_runner.py` |
+
+---
+
+# 4. Invariants
+
+| Surface | Invariant | Verification |
+|---------|-----------|--------------|
+| CLI behavior | Identical outputs and execution path | smoke tests |
+| API responses | No schema changes | tests |
+| Processing results | Byte-identical outputs | golden comparison |
+| Runtime state | No side effects introduced | test suite |
+| CI coverage | ≥ 40% | CI gate |
+
+---
+
+# 5. Implementation Steps
+
+## Step 1 — Create runner module
+
+Create `modules/runtime/runner.py`:
+
+```python
+class ProcessingRequest:
+    def __init__(self, processing):
+        self.processing = processing
+
+class ProcessingRunner:
+    def run(self, request):
+        from modules.processing import process_images_inner
+        return process_images_inner(request.processing)
+```
+
+## Step 2 — Wire process_images
+
+Inside `process_images`, replace:
+
+```python
+res = process_images_inner(p)
+```
+
+With:
+
+```python
+from modules.runtime.runner import ProcessingRunner, ProcessingRequest
+runner = ProcessingRunner()
+request = ProcessingRequest(p)
+res = runner.run(request)
+```
+
+## Step 3 — Add contract test
+
+Add `test/quality/test_processing_runner.py` with delegation test.
+
+---
+
+# 6. Risk & Rollback Plan
+
+Risk level: **Low**
+
+Mechanical refactor. Rollback: revert wiring commit.
+
+---
+
+# 7. Deliverables
+
+Code: `modules/runtime/runner.py`, wiring in `process_images`
+Tests: `test/quality/test_processing_runner.py`
+Docs: M10_toolcalls.md, M10_run1.md, M10_summary.md, M10_audit.md
+Ledger: Update `docs/serena.md`
+Tag: `v0.0.10-m10`

docs/milestones/M10/M10_toolcalls.md

@@ -0,0 +1,11 @@
+# M10 Toolcalls — ProcessingRunner Skeleton
+
+Implementation toolcalls for Cursor execution.
+
+| Timestamp | Tool | Purpose | Files/Target | Status |
+|-----------|------|---------|--------------|--------|
+| 2026-03-11 | write | Create M10_plan.md, M10_toolcalls.md | docs/milestones/M10/ | done |
+| 2026-03-11 | write | Create modules/runtime/runner.py | modules/runtime/ | done |
+| 2026-03-11 | search_replace | Wire process_images to delegate through runner | modules/processing.py | done |
+| 2026-03-11 | write | Add contract test for ProcessingRunner | test/quality/test_processing_runner.py | done |
+| 2026-03-11 | run | Create branch m10-processing-runner | git | in_progress |