feat: replace Aider with secure mini-SWE-agent worker

src/lai_automation/policy.py

@@ -1,84 +1,63 @@
 from __future__ import annotations
 
-from dataclasses import dataclass
-from pathlib import Path, PurePosixPath
+from pathlib import PurePosixPath
 
 from .config import Settings
-from .git import ChangeSummary
-from .models import FailureReport
+from .git import GitWorkspace
+from .models import ChangeSummary
 
-_ALWAYS_DENIED = (
-    ".env",
-    "vendor/",
-    "storage/",
+_PROTECTED_PARTS = {".git", "vendor", "node_modules", "storage"}
+_PROTECTED_PREFIXES = (
+    ".gitea/",
     "bootstrap/cache/",
     "docker/",
-    "docker-compose",
-    ".gitea/",
-    ".github/",
-    ".aider",
-)
-
-_DIRECT_MAIN_DENIED = (
-    "database/migrations/",
-    "app/Http/Middleware/",
-    "app/Models/User.php",
-    "app/Services/PermissionService.php",
-    "app/Services/SQLValidatorService.php",
-    "config/auth.php",
-    "config/database.php",
-    "routes/",
 )
+_PROTECTED_FILES = {
+    "Dockerfile",
+    "docker-compose.yml",
+    "docker-compose.yaml",
+    "compose.yml",
+    "compose.yaml",
+}
+_CODE_SUFFIXES = {".php", ".js", ".ts", ".vue", ".css", ".py"}
 
 
-@dataclass(frozen=True)
-class PolicyResult:
-    allowed: bool
-    errors: tuple[str, ...]
-
-
-def evaluate_changes(
+def validate_changes(
+    workspace: GitWorkspace,
     summary: ChangeSummary,
     settings: Settings,
-    workspace: Path | None = None,
-) -> PolicyResult:
-    errors: list[str] = []
+) -> None:
+    if workspace.has_path(".git"):
+        raise ValueError("The agent created forbidden Git metadata in the worktree")
     if not summary.files:
-        errors.append("Agent produced no file changes")
-    elif all(filename.startswith("tests/") for filename in summary.files):
-        errors.append("Agent changed only tests; production behavior was not fixed")
+        raise ValueError("The agent did not produce a change")
     if len(summary.files) > settings.max_changed_files:
-        errors.append(f"Changed {len(summary.files)} files; limit is {settings.max_changed_files}")
+        raise ValueError(
+            f"Changed file limit exceeded "
+            f"({len(summary.files)} > {settings.max_changed_files})"
+        )
     if summary.changed_lines > settings.max_changed_lines:
-        errors.append(f"Changed {summary.changed_lines} lines; limit is {settings.max_changed_lines}")
-
-    for filename in summary.files:
-        if PurePosixPath(filename).is_absolute() or ".." in PurePosixPath(filename).parts:
-            errors.append(f"Invalid changed path: {filename}")
-            continue
-        if workspace and (workspace / filename).is_symlink():
-            errors.append(f"Symbolic links are not allowed: {filename}")
-            continue
-        if any(filename == prefix or filename.startswith(prefix) for prefix in _ALWAYS_DENIED):
-            errors.append(f"Denied path changed: {filename}")
-        if settings.mode == "direct-main" and any(
-            filename == prefix or filename.startswith(prefix) for prefix in _DIRECT_MAIN_DENIED
-        ):
-            errors.append(f"Direct-main denied path changed: {filename}")
-
-    return PolicyResult(not errors, tuple(errors))
-
-
-def evaluate_report_scope(report: FailureReport, summary: ChangeSummary) -> PolicyResult:
-    expected = f"{report.user_feedback or ''}\n{report.expected_behavior or ''}".lower()
-    requires_cross_database_orchestration = (
-        "cockpit_config" in expected and ("fk_" in expected or "erp" in expected)
-    )
-    has_application_change = any(filename.startswith("app/") for filename in summary.files)
-    errors = []
-    if requires_cross_database_orchestration and not has_application_change:
-        errors.append(
-            "Cross-database report changed no application code; inspect routing and implement staged orchestration"
+        raise ValueError(
+            f"Changed line limit exceeded "
+            f"({summary.changed_lines} > {settings.max_changed_lines})"
         )
 
-    return PolicyResult(not errors, tuple(errors))
+    code_changed = False
+    for raw_name in summary.files:
+        name = raw_name.replace("\\", "/")
+        path = PurePosixPath(name)
+        if name.startswith("/") or ".." in path.parts:
+            raise ValueError(f"Unsafe changed path: {name}")
+        if name.startswith(".env") or path.name.startswith(".env"):
+            raise ValueError(f"Protected environment file changed: {name}")
+        if path.parts and path.parts[0] in _PROTECTED_PARTS:
+            raise ValueError(f"Protected path changed: {name}")
+        if name in _PROTECTED_FILES or name.startswith(_PROTECTED_PREFIXES):
+            raise ValueError(f"Protected deployment path changed: {name}")
+        if workspace.has_symlink(name):
+            raise ValueError(f"Symbolic links are not allowed in agent changes: {name}")
+        if path.suffix in _CODE_SUFFIXES and not name.startswith(("tests/", "docs/")):
+            code_changed = True
+
+    if not code_changed:
+        raise ValueError("The agent must change at least one application source file")