refactor: phase 0 guardrails + phase 1 step 2 (models.py split)

Squash of branch refactor/phase0-guardrails-and-models-split — 4 commits,
81 files, 173/173 pytest green, OpenAPI contract preserved (360 paths /
484 operations).

## Phase 0 — Architecture guardrails

Three defense-in-depth layers to keep the architecture rules enforced
regardless of who opens Claude Code in this repo:

  1. .claude/settings.json PreToolUse hook on Write/Edit blocks any file
     that would exceed the 500-line hard cap. Auto-loads in every Claude
     session in this repo.
  2. scripts/githooks/pre-commit (install via scripts/install-hooks.sh)
     enforces the LOC cap locally, freezes migrations/ without
     [migration-approved], and protects guardrail files without
     [guardrail-change].
  3. .gitea/workflows/ci.yaml gains loc-budget + guardrail-integrity +
     sbom-scan (syft+grype) jobs, adds mypy --strict for the new Python
     packages (compliance/{services,repositories,domain,schemas}), and
     tsc --noEmit for admin-compliance + developer-portal.

Per-language conventions documented in AGENTS.python.md, AGENTS.go.md,
AGENTS.typescript.md at the repo root — layering, tooling, and explicit
"what you may NOT do" lists. Root CLAUDE.md is prepended with the six
non-negotiable rules. Each of the 10 services gets a README.md.

scripts/check-loc.sh enforces soft 300 / hard 500 and surfaces the
current baseline of 205 hard + 161 soft violations so Phases 1-4 can
drain it incrementally. CI gates only CHANGED files in PRs so the
legacy baseline does not block unrelated work.

## Deprecation sweep

47 files. Pydantic V1 regex= -> pattern= (2 sites), class Config ->
ConfigDict in source_policy_router.py (schemas.py intentionally skipped;
it is the Phase 1 Step 3 split target). datetime.utcnow() ->
datetime.now(timezone.utc) everywhere including SQLAlchemy default=
callables. All DB columns already declare timezone=True, so this is a
latent-bug fix at the Python side, not a schema change.

DeprecationWarning count dropped from 158 to 35.

## Phase 1 Step 1 — Contract test harness

tests/contracts/test_openapi_baseline.py diffs the live FastAPI /openapi.json
against tests/contracts/openapi.baseline.json on every test run. Fails on
removed paths, removed status codes, or new required request body fields.
Regenerate only via tests/contracts/regenerate_baseline.py after a
consumer-updated contract change. This is the safety harness for all
subsequent refactor commits.

## Phase 1 Step 2 — models.py split (1466 -> 85 LOC shim)

compliance/db/models.py is decomposed into seven sibling aggregate modules
following the existing repo pattern (dsr_models.py, vvt_models.py, ...):

  regulation_models.py       (134) — Regulation, Requirement
  control_models.py          (279) — Control, Mapping, Evidence, Risk
  ai_system_models.py        (141) — AISystem, AuditExport
  service_module_models.py   (176) — ServiceModule, ModuleRegulation, ModuleRisk
  audit_session_models.py    (177) — AuditSession, AuditSignOff
  isms_governance_models.py  (323) — ISMSScope, Context, Policy, Objective, SoA
  isms_audit_models.py       (468) — Finding, CAPA, MgmtReview, InternalAudit,
                                     AuditTrail, Readiness

models.py becomes an 85-line re-export shim in dependency order so
existing imports continue to work unchanged. Schema is byte-identical:
__tablename__, column definitions, relationship strings, back_populates,
cascade directives all preserved.

All new sibling files are under the 500-line hard cap; largest is
isms_audit_models.py at 468. No file in compliance/db/ now exceeds
the hard cap.

## Phase 1 Step 3 — infrastructure only

backend-compliance/compliance/{schemas,domain,repositories}/ packages
are created as landing zones with docstrings. compliance/domain/
exports DomainError / NotFoundError / ConflictError / ValidationError /
PermissionError — the base classes services will use to raise
domain-level errors instead of HTTPException.

PHASE1_RUNBOOK.md at backend-compliance/PHASE1_RUNBOOK.md documents
the nine-step execution plan for Phase 1: snapshot baseline,
characterization tests, split models.py (this commit), split schemas.py
(next), extract services, extract repositories, mypy --strict, coverage.

## Verification

  backend-compliance/.venv-phase1: uv python install 3.12 + pip -r requirements.txt
  PYTHONPATH=. pytest compliance/tests/ tests/contracts/
  -> 173 passed, 0 failed, 35 warnings, OpenAPI 360/484 unchanged

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.claude/CLAUDE.md

@@ -1,5 +1,17 @@
 # BreakPilot Compliance - DSGVO/AI-Act SDK Platform
 
+> **NON-NEGOTIABLE STRUCTURE RULES** (enforced by `.claude/settings.json` hook, git pre-commit, and CI):
+> 1. **File-size budget:** soft target **300** lines, **hard cap 500** lines for any non-test, non-generated source file. Anything larger → split it. Exceptions are listed in `.claude/rules/loc-exceptions.txt` and require a written rationale.
+> 2. **Clean architecture per service.** Routers/handlers stay thin (≤30 lines per handler) and delegate to services; services use repositories; repositories own DB I/O. See `AGENTS.python.md` / `AGENTS.go.md` / `AGENTS.typescript.md`.
+> 3. **Do not touch the database schema.** No new Alembic migrations, no `ALTER TABLE`, no model field renames without an explicit migration plan reviewed by the DB owner. SQLAlchemy `__tablename__` and column names are frozen.
+> 4. **Public endpoints are a contract.** Any change to a path, method, status code, request schema, or response schema in `backend-compliance/`, `ai-compliance-sdk/`, `dsms-gateway/`, `document-crawler/`, or `compliance-tts-service/` must be accompanied by a matching update in **every** consumer (`admin-compliance/`, `developer-portal/`, `breakpilot-compliance-sdk/`, `consent-sdk/`). Use the OpenAPI snapshot tests in `tests/contracts/` as the gate.
+> 5. **Tests are not optional.** New code without tests fails CI. Refactors must preserve coverage and add a characterization test before splitting an oversized file.
+> 6. **Do not bypass the guardrails.** Do not edit `.claude/settings.json`, `scripts/check-loc.sh`, or the loc-exceptions list to silence violations. If a rule is wrong, raise it in a PR description.
+>
+> These rules apply to **every** Claude Code session opened inside this repository, regardless of who launched it. They are loaded automatically via this `CLAUDE.md`.
+
+
+
 ## Entwicklungsumgebung (WICHTIG - IMMER ZUERST LESEN)
 
 ### Zwei-Rechner-Setup + Hetzner

.claude/rules/architecture.md

@@ -0,0 +1,43 @@
+# Architecture Rules (auto-loaded)
+
+These rules apply to **every** Claude Code session in this repository, regardless of who launched it. They are non-negotiable.
+
+## File-size budget
+
+- **Soft target:** 300 lines per non-test, non-generated source file.
+- **Hard cap:** 500 lines. The PreToolUse hook in `.claude/settings.json` blocks Write/Edit operations that would create or push a file past 500. The git pre-commit hook re-checks. CI is the final gate.
+- Exceptions live in `.claude/rules/loc-exceptions.txt` and require a written rationale plus `[guardrail-change]` in the commit message. The exceptions list should shrink over time, not grow.
+
+## Clean architecture
+
+- Python (FastAPI): see `AGENTS.python.md`. Layering: `api → services → repositories → db.models`. Routers ≤30 LOC per handler. Schemas split per domain.
+- Go (Gin): see `AGENTS.go.md`. Standard Go Project Layout + hexagonal. `cmd/` thin, wiring in `internal/app`.
+- TypeScript (Next.js): see `AGENTS.typescript.md`. Server-by-default, push the client boundary deep, colocate `_components/` and `_hooks/` per route.
+
+## Database is frozen
+
+- No new Alembic migrations. No `ALTER TABLE`. No `__tablename__` or column renames.
+- The pre-commit hook blocks any change under `migrations/` or `alembic/versions/` unless the commit message contains `[migration-approved]`.
+
+## Public endpoints are a contract
+
+- Any change to a path/method/status/request schema/response schema in a backend service must update every consumer in the same change set.
+- Each backend service has an OpenAPI baseline at `tests/contracts/openapi.baseline.json`. Contract tests fail on drift.
+
+## Tests
+
+- New code without tests fails CI.
+- Refactors must preserve coverage. Before splitting an oversized file, add a characterization test that pins current behavior.
+- Layout: `tests/unit/`, `tests/integration/`, `tests/contracts/`, `tests/e2e/`.
+
+## Guardrails are themselves protected
+
+- Edits to `.claude/settings.json`, `scripts/check-loc.sh`, `scripts/githooks/pre-commit`, `.claude/rules/loc-exceptions.txt`, or any `AGENTS.*.md` require `[guardrail-change]` in the commit message. The pre-commit hook enforces this.
+- If you (Claude) think a rule is wrong, surface it to the user. Do not silently weaken it.
+
+## Tooling baseline
+
+- Python: `ruff`, `mypy --strict` on new modules, `pytest --cov`.
+- Go: `golangci-lint` strict config, `go vet`, table-driven tests.
+- TS: `tsc --noEmit` strict, ESLint type-aware, Vitest, Playwright.
+- All three: dependency caching in CI, license/SBOM scan via `syft`+`grype`.

.claude/rules/loc-exceptions.txt

@@ -0,0 +1,8 @@
+# loc-exceptions.txt — files allowed to exceed the 500-line hard cap.
+#
+# Format: one repo-relative path per line. Comments start with '#' and are ignored.
+# Each exception MUST be preceded by a comment explaining why splitting is not viable.
+#
+# Phase 0 baseline: this list is initially empty. Phases 1-4 will add grandfathered
+# entries as we encounter legitimate exceptions (e.g. large generated data tables).
+# The goal is for this list to SHRINK over time, never grow.

.claude/settings.json

@@ -0,0 +1,28 @@
+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Write",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "f=$(jq -r '.tool_input.file_path // empty'); [ -z \"$f\" ] && exit 0; lines=$(printf '%s' \"$(jq -r '.tool_input.content // empty')\" | awk 'END{print NR}'); if [ \"${lines:-0}\" -gt 500 ]; then echo '{\"decision\":\"block\",\"reason\":\"breakpilot guardrail: file exceeds the 500-line hard cap. Split it into smaller modules per the layering rules in AGENTS.<lang>.md. If this is generated/data code, add an entry to .claude/rules/loc-exceptions.txt with rationale and reference [guardrail-change].\"}'; exit 0; fi",
+            "shell": "bash",
+            "timeout": 5
+          }
+        ]
+      },
+      {
+        "matcher": "Edit",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "f=$(jq -r '.tool_input.file_path // empty'); [ -z \"$f\" ] || [ ! -f \"$f\" ] && exit 0; case \"$f\" in *.md|*.json|*.yaml|*.yml|*test*|*tests/*|*node_modules/*|*.next/*|*migrations/*) exit 0 ;; esac; new_str=$(jq -r '.tool_input.new_string // empty'); old_str=$(jq -r '.tool_input.old_string // empty'); old_lines=$(printf '%s' \"$old_str\" | awk 'END{print NR}'); new_lines=$(printf '%s' \"$new_str\" | awk 'END{print NR}'); cur=$(wc -l < \"$f\" | tr -d ' '); proj=$((cur - old_lines + new_lines)); if [ \"$proj\" -gt 500 ]; then echo \"{\\\"decision\\\":\\\"block\\\",\\\"reason\\\":\\\"breakpilot guardrail: this edit would push $f to ~$proj lines (hard cap is 500). Split the file before continuing. See AGENTS.<lang>.md for the layering rules.\\\"}\"; fi; exit 0",
+            "shell": "bash",
+            "timeout": 5
+          }
+        ]
+      }
+    ]
+  }
+}