feat(cre): source tree skeleton with empty module dirs and CI workflow

- src/cre.cr entry point + version.cr
- Empty module dirs: cli, tui, engine, events, rotators, policy, audit, crypto, persistence, notifiers, compliance, config, domain, aws, vault, github, demo
- spec/ unit + integration + fixtures structure mirroring src/
- spec_helper.cr with stdlib spec + cre require
- GitHub Actions CI: format, unit matrix (Crystal 1.19/1.20/nightly x ubuntu/macos), integration with PG service, build job

PROJECTS/intermediate/credential-rotation-enforcer/.github/workflows/ci.yml

@@ -0,0 +1,73 @@
+# ©AngelaMos | 2026
+# ci.yml
+
+name: CI - Credential Rotation Enforcer
+
+on:
+  push:
+    paths:
+      - 'PROJECTS/intermediate/credential-rotation-enforcer/**'
+      - '.github/workflows/cre-*.yml'
+  pull_request:
+    paths:
+      - 'PROJECTS/intermediate/credential-rotation-enforcer/**'
+
+defaults:
+  run:
+    working-directory: PROJECTS/intermediate/credential-rotation-enforcer
+
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: crystal-lang/install-crystal@v1
+        with:
+          crystal: 1.20.0
+      - run: crystal tool format --check
+
+  unit:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+        crystal: ["1.19.0", "1.20.0", "nightly"]
+    steps:
+      - uses: actions/checkout@v4
+      - uses: crystal-lang/install-crystal@v1
+        with:
+          crystal: ${{ matrix.crystal }}
+      - run: shards install
+      - run: crystal spec spec/unit --order=random
+
+  integration:
+    runs-on: ubuntu-latest
+    services:
+      postgres:
+        image: postgres:16
+        env:
+          POSTGRES_USER: cre_test
+          POSTGRES_PASSWORD: cre_test
+          POSTGRES_DB: cre_test
+        ports: [5432:5432]
+        options: --health-cmd "pg_isready -U cre_test" --health-interval 10s
+    env:
+      DATABASE_URL: postgres://cre_test:cre_test@localhost:5432/cre_test
+    steps:
+      - uses: actions/checkout@v4
+      - uses: crystal-lang/install-crystal@v1
+        with:
+          crystal: 1.20.0
+      - run: shards install
+      - run: crystal spec spec/integration --order=random
+
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: crystal-lang/install-crystal@v1
+        with:
+          crystal: 1.20.0
+      - run: shards install
+      - run: shards build cre --release

PROJECTS/intermediate/credential-rotation-enforcer/spec/spec_helper.cr

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+# ===================
+# ©AngelaMos | 2026
+# spec_helper.cr
+# ===================
+
+require "spec"
+require "../src/cre"

PROJECTS/intermediate/credential-rotation-enforcer/src/cre.cr

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+# ===================
+# ©AngelaMos | 2026
+# cre.cr
+# ===================
+
+require "./cre/version"
+
+module CRE
+  def self.main(argv : Array(String)) : Int32
+    0
+  end
+end
+
+if PROGRAM_NAME.includes?("cre")
+  exit CRE.main(ARGV)
+end

PROJECTS/intermediate/credential-rotation-enforcer/src/cre/version.cr

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+# ===================
+# ©AngelaMos | 2026
+# version.cr
+# ===================
+
+module CRE
+  VERSION = "0.1.0"
+end