Refactor project with registry/facade/strategy patterns

Replace utils/ tree with core/ (ActionRegistry, ActionExecutor,
CallbackExecutor, PackageLoader, json_store) and split local/, remote/,
server/, project/, utils/ into flat strategy modules. Harden TCP server
with loopback-only default, add SSRF guard for HTTP downloads, fix
rename_file overwrite and related bugs. Replace six per-version
workflows with matrix ci-dev.yml / ci-stable.yml. Add 80-case pytest
suite, CLAUDE.md, Sphinx docs, and README with embedded architecture
diagram.

Author: JE-Chen

.github/workflows/ci-dev.yml

@@ -0,0 +1,34 @@
+name: CI (dev)
+
+on:
+  push:
+    branches: [ "dev" ]
+  pull_request:
+    branches: [ "dev" ]
+  schedule:
+    - cron: "0 3 * * *"
+
+permissions:
+  contents: read
+
+jobs:
+  pytest:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: [ "3.10", "3.11", "3.12" ]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+          cache: pip
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip wheel
+          pip install -r dev_requirements.txt
+          pip install pytest
+      - name: Run pytest
+        run: python -m pytest tests/ -v --tb=short

.github/workflows/ci-stable.yml

@@ -0,0 +1,34 @@
+name: CI (stable)
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+  schedule:
+    - cron: "0 3 * * *"
+
+permissions:
+  contents: read
+
+jobs:
+  pytest:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: [ "3.10", "3.11", "3.12" ]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+          cache: pip
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip wheel
+          pip install -r requirements.txt
+          pip install pytest
+      - name: Run pytest
+        run: python -m pytest tests/ -v --tb=short

.github/workflows/file_automation_dev_python3_10.yml

@@ -156,3 +156,5 @@ token.json
 credentials.json
 **/token.json
 **/credentials.json
+
+.claude/