fix #475: guide Windows shell execution and report quoting hazards

.github/workflows/windows-shell.yml

@@ -0,0 +1,26 @@
+name: Windows shell regressions
+
+on:
+  push:
+    paths:
+      - 'app/data/action/run_shell.py'
+      - 'agent_core/core/prompts/context.py'
+      - 'tests/windows_shell/**'
+      - '.github/workflows/windows-shell.yml'
+  pull_request:
+    paths:
+      - 'app/data/action/run_shell.py'
+      - 'agent_core/core/prompts/context.py'
+      - 'tests/windows_shell/**'
+      - '.github/workflows/windows-shell.yml'
+
+jobs:
+  shell:
+    runs-on: windows-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+      - name: Verify real cmd, Windows PowerShell and pwsh execution
+        run: python -m unittest discover -s tests/windows_shell -v

agent_core/core/prompts/context.py

@@ -171,6 +171,13 @@
 - User Location: {user_location}
 - Current Working Directory: {working_directory}
 - Operating System: {operating_system} {os_version} ({os_platform})
+On Windows, run_shell defaults to cmd. For PowerShell source select shell="powershell"
+or "pwsh" and submit the raw script; run_shell launches the interpreter. For example,
+command="Get-CimInstance Win32_LogicalDisk -Filter 'DriveType=3'" with shell="powershell".
+Omit powershell -Command and cmd /c wrappers unless nesting is intentional. Read
+run_shell's guidance and verify stdout even on success; nested quoting can silently
+change the result. After a quoting failure, check the selected shell and partial
+side effects before correcting the source. Avoid repeated escape-character guesses.
 </agent_environment>
 """