Implement Stage A: rule engine, validation, audit, and safety gates

Completes 109 of 121 tasks. Every remaining task needs a tenant connection
(T055, T056, T101-T103) or an Azure Automation account (T115-T121).

  354 offline Pester tests      PASS
  Engine purity (Principle IV)  PASS
  Sanitization (SC-013)         PASS  (156 files)
  Graph module loaded in tests  none  (SC-008 holds)

What landed
  - Four-layer configuration validation with stable finding codes, covering
    every VR-002 and VR-003 condition, plus a 23-fixture invalid-config corpus
  - Run loop, audit records (NDJSON through a single sink), summaries,
    reconciliation, and exit codes 0-6
  - Persistence behind a single write-body builder whose result always has
    exactly one key
  - Invoke-PersonaEngine.ps1 and Edit-PersonaEngineConfig.ps1
  - Six docs, two pipelines, traceability matrix, V-5a and sanitization records

Three deviations from tasks.md, each recorded in its status block

  T033 is not in Resolve-UserPersona. evaluationErrorThreshold is run-level
  state and the rule engine is pure; a counter there would break Principle IV.
  It lives in New-PersonaRunCounter and is applied in the run loop.

  A new src/Engine/ layer holds Invoke-PersonaEngineRun. The entry script
  imports the manifest, which requires Microsoft.Graph.Authentication, so a
  loop living only inside it could not run on a machine without the Graph SDK
  and SC-004 could not be proven at all. The entry script is now a thin
  wrapper and what ships is what is tested.

  The invalid-config corpus is generated by a committed script, with the
  generated fixtures committed too, so a reviewer sees the fixture in the diff.

Defects found by running the code, not by reading it

  Group and role ID lists were double-wrapped: @(Get-PersonaGroupIdPage ...)
  around a comma-returned array collapsed every membership list into one
  bogus space-joined entry. That is a silent false non-match, exactly what
  FR-013 exists to prevent.

  A 403 whose status appears only in the exception message parsed as $null,
  which the retry policy treats as a transport error - five requests per
  account against a tenant already refusing. Status extraction now falls back
  to the message text, bounded to 400-599.

  The sanitization scan walked tracked files only, so it covered 34 of 156
  files and none of this phase's code. It now scans untracked non-ignored
  files too, and a negative control confirms it catches a planted leak.

  Test-Json reports one error per violating location, not first-failure-only
  as the V-5a draft claimed. Record and pin corrected.

Enforcement remains blocked on the V-4 security sign-off.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

tests/RuleEngine/Composition.Tests.ps1

@@ -0,0 +1,107 @@
+#Requires -Modules @{ ModuleName = 'Pester'; ModuleVersion = '5.0.0' }
+
+BeforeAll {
+    $repoRoot = Split-Path (Split-Path $PSScriptRoot -Parent) -Parent
+    foreach ($f in @(
+            'src/Normalization/New-PersonaMembershipRecord.ps1'
+            'src/Normalization/New-PersonaUserRecord.ps1'
+            'src/RuleEngine/Test-PersonaCondition.ps1'
+            'src/RuleEngine/Test-PersonaConditionGroup.ps1'
+        )) { . (Join-Path $repoRoot $f) }
+
+    $script:user = New-PersonaUserRecord `
+        -AccountObjectId '00000000-0000-0000-0000-000000000101' `
+        -UserPrincipalName 'svc-billing@example.invalid' `
+        -UserType 'Member' `
+        -Properties @{ Department = 'Finance'; JobTitle = 'Analyst' }
+
+    function Cond {
+        param([string] $Property, [string] $Operator = 'equals', [string] $Value)
+        [pscustomobject]@{ type = 'property'; property = $Property; operator = $Operator; value = $Value }
+    }
+
+    function New-ConditionGroup {
+        param([string] $Operator, [object[]] $Conditions)
+        [pscustomobject]@{ operator = $Operator; conditions = $Conditions }
+    }
+
+    # Builds exactly $Depth nested groups around a leaf condition that is always
+    # true. Leaf conditions do not add a level: the engine counts group nesting,
+    # so -Depth 3 yields group(group(group(leaf))) and evaluates at depths 1..3.
+    function New-NestedGroup {
+        param([int] $Depth)
+        $node = Cond -Property 'Department' -Value 'Finance'
+        for ($i = 0; $i -lt $Depth; $i++) {
+            $node = New-ConditionGroup -Operator 'all' -Conditions @($node)
+        }
+        $node
+    }
+}
+
+Describe 'Logical composition (RE-003)' {
+
+    Context 'all' {
+        It 'is true when every condition is true' {
+            Test-PersonaConditionGroup -Group (New-ConditionGroup 'all' @((Cond 'Department' -Value 'Finance'), (Cond 'JobTitle' -Value 'Analyst'))) -UserRecord $user | Should -Be 'True'
+        }
+        It 'is false when any condition is false' {
+            Test-PersonaConditionGroup -Group (New-ConditionGroup 'all' @((Cond 'Department' -Value 'Finance'), (Cond 'JobTitle' -Value 'Manager'))) -UserRecord $user | Should -Be 'False'
+        }
+    }
+
+    Context 'any' {
+        It 'is true when at least one condition is true' {
+            Test-PersonaConditionGroup -Group (New-ConditionGroup 'any' @((Cond 'Department' -Value 'Legal'), (Cond 'JobTitle' -Value 'Analyst'))) -UserRecord $user | Should -Be 'True'
+        }
+        It 'is false when every condition is false' {
+            Test-PersonaConditionGroup -Group (New-ConditionGroup 'any' @((Cond 'Department' -Value 'Legal'), (Cond 'JobTitle' -Value 'Manager'))) -UserRecord $user | Should -Be 'False'
+        }
+    }
+
+    Context 'nesting' {
+        It 'resolves an any group nested inside an all group' {
+            $inner = New-ConditionGroup 'any' @((Cond 'JobTitle' -Value 'Manager'), (Cond 'JobTitle' -Value 'Analyst'))
+            $outer = New-ConditionGroup 'all' @((Cond 'Department' -Value 'Finance'), $inner)
+            Test-PersonaConditionGroup -Group $outer -UserRecord $user | Should -Be 'True'
+        }
+
+        It 'resolves an all group nested inside an any group' {
+            $inner = New-ConditionGroup 'all' @((Cond 'Department' -Value 'Legal'), (Cond 'JobTitle' -Value 'Analyst'))
+            $outer = New-ConditionGroup 'any' @((Cond 'Department' -Value 'Finance'), $inner)
+            Test-PersonaConditionGroup -Group $outer -UserRecord $user | Should -Be 'True'
+        }
+    }
+
+    Context 'empty and malformed groups' {
+        It 'returns Unknown for an empty conditions collection' {
+            Test-PersonaConditionGroup -Group (New-ConditionGroup 'all' @()) -UserRecord $user | Should -Be 'Unknown'
+        }
+        It 'returns Unknown for an unrecognized group operator' {
+            Test-PersonaConditionGroup -Group (New-ConditionGroup 'either' @((Cond 'Department' -Value 'Finance'))) -UserRecord $user | Should -Be 'Unknown'
+        }
+    }
+}
+
+Describe 'Depth limits (RE-004)' {
+
+    It 'evaluates a tree exactly at the configured depth' {
+        Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 5) -UserRecord $user -MaxDepth 5 | Should -Be 'True'
+    }
+
+    It 'returns Unknown beyond the configured depth rather than truncating' {
+        # Silent truncation would evaluate a rule the author did not write.
+        Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 7) -UserRecord $user -MaxDepth 5 | Should -Be 'Unknown'
+    }
+
+    It 'honours a lowered depth limit' {
+        Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 3) -UserRecord $user -MaxDepth 2 | Should -Be 'Unknown'
+    }
+
+    It 'rejects a MaxDepth above the hard ceiling of 10' {
+        { Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 2) -UserRecord $user -MaxDepth 11 } | Should -Throw
+    }
+
+    It 'rejects a MaxDepth below the minimum of 1' {
+        { Test-PersonaConditionGroup -Group (New-NestedGroup -Depth 2) -UserRecord $user -MaxDepth 0 } | Should -Throw
+    }
+}