docs: add phase 1 sprint contracts

PROGRESS.md

@@ -17,6 +17,47 @@ The project is in documentation and readiness planning. Solver implementation ha
 
 ## Completed Work
 
+### 2026-05-01 - P1-00 Phase 1 sprint contracts generated
+Author: Codex
+
+Changed files:
+- `phases/index.json`
+- `phases/1-linear-static-mitc4/index.json`
+- `phases/1-linear-static-mitc4/step0.md`
+- `phases/1-linear-static-mitc4/step1.md`
+- `phases/1-linear-static-mitc4/step2.md`
+- `phases/1-linear-static-mitc4/step3.md`
+- `phases/1-linear-static-mitc4/step4.md`
+- `phases/1-linear-static-mitc4/step5.md`
+- `phases/1-linear-static-mitc4/step6.md`
+- `phases/1-linear-static-mitc4/step7.md`
+- `phases/1-linear-static-mitc4/step8.md`
+- `phases/1-linear-static-mitc4/step9.md`
+- `phases/1-linear-static-mitc4/step10.md`
+- `phases/1-linear-static-mitc4/step11.md`
+- `phases/1-linear-static-mitc4/step12.md`
+- `phases/1-linear-static-mitc4/step13.md`
+- `phases/1-linear-static-mitc4/step14.md`
+- `phases/1-linear-static-mitc4/step15.md`
+- `PLAN.md`
+- `PROGRESS.md`
+
+Summary:
+- Converted Phase 1 milestones P1-01 through P1-16 into executable Harness step files under `phases/1-linear-static-mitc4`.
+- Added top-level and phase-level JSON indices using the zero-based `scripts/execute.py` convention.
+- Embedded sprint contracts in every step with objective, required reading, scope, allowed files, explicit non-goals, tests to write first, reference-artifact policy, acceptance command, evaluator checklist, and handoff requirements.
+- Kept readiness blockers visible, especially MITC4 formulation decisions, build-system selection, reference comparator tolerance, missing reaction CSV, and the need for Phase 1-compatible `TYPE=S4` references.
+- Updated `PLAN.md` so new agents can find and execute the active phase files.
+
+Verification:
+- Parsed `phases/index.json` and `phases/1-linear-static-mitc4/index.json` with PowerShell `ConvertFrom-Json`.
+- Verified the phase registry points to `1-linear-static-mitc4`, all 16 steps are `pending`, step names are kebab-case, and every `stepN.md` file exists.
+- Verified every step file includes the required sprint contract sections from `docs/HARNESS_ENGINEERING.md`.
+- `python scripts/validate_workspace.py` exited successfully, but still reported no configured validation commands.
+
+Follow-up:
+- Begin Phase 1 execution with `python scripts/execute.py 1-linear-static-mitc4` after confirming readiness blockers are accepted, resolved, or intentionally deferred.
+
 ### 2026-05-01 - Phase 1 implementation master plan added
 Author: Codex