Update GEMINI.md with Vim folding mandate and add test cases for set-flag-format CLI command

GEMINI.md

@@ -10,15 +10,16 @@ The primary goal is to use the context of CTF challenges (forensics, crypto, web
 2. **Focus on Explanation:** Prioritize high-signal explanations of Python mechanics, libraries, and documentation.
 3. **Summarization:** When directed, summarize documentation (local or web-based) to aid in understanding CTF tools and Python modules.
 4. **Educational Context:** Use the existing scripts and tools in this repository (like `psk_crack.py`, `exploit.sh`, or the `tools/` directory) as examples when explaining technical concepts.
+5. **Vim Folding Markers:** Wrap all classes, command groups, subcommands, and functions inside project implementation files in standard Vim/Neovim folding syntax markers (`# {{{ <name>` and `# }}}`).
 
 ## Interaction Workflow
 When discussing new implementations, features, or additions:
 1. **Discussion**: Discuss implementation details and potential approaches.
 2. **The Pitch**: Provide a clear, technical pitch detailing the planned code modifications.
 3. **Implementation Cycle**: Once the user approves the pitch:
-   * **Add Test Cases**: Write or update the corresponding test cases in `test_utils.py` following the SDET instructions.
-   * **Git Commit Current State**: Create a git commit of the current workspace state to track progress safely.
-   * **Update the Codebase**: Write/update the actual project implementation files as approved.
+   * **Add Test Cases**: Write or update the corresponding test cases in the test files (e.g. `tests/test_forensics.py`) following the SDET instructions.
+   * **Git Commit Current State**: Create a git commit of the current workspace state (including the new tests) *before* modifying any implementation files.
+   * **Update the Codebase**: Write/update the actual project implementation files as approved. Do **NOT** create a git commit after writing this implementation code. This ensures all implementation changes remain unstaged so the user can easily run `git diff` to review them.
 
 ## Python Learning Objectives
 - Understanding standard library modules relevant to security (e.g., `os`, `sys`, `base64`, `hashlib`).

tests/test_forensics.py

@@ -295,3 +295,29 @@ def test_forensics_flag_detect_cli_not_found():
     result = runner.invoke(forensics_group, ["flag-detect", str(test_file)])
     assert result.exit_code == 0
     assert "No flag patterns found" in result.output
+
+def test_set_flag_format_cli():
+    """
+    Verifies that 'set-flag-format' CLI command writes the pattern to config.toml.
+    """
+    from ctf.commands import set_flag_format
+    from ctf.utils import load_config
+    
+    runner = CliRunner()
+    config_file = Path("/home/venus/code/ctf/config.toml")
+    
+    # Save the original config to restore later
+    original_config = load_config(str(config_file))
+    
+    try:
+        result = runner.invoke(set_flag_format, ["TEST_FLAG{[a-z]+}"])
+        assert result.exit_code == 0
+        assert "Flag format set to" in result.output
+        
+        # Verify it was written to config.toml
+        updated_config = load_config(str(config_file))
+        assert updated_config["Competition"]["flag_format"] == "TEST_FLAG{[a-z]+}"
+    finally:
+        # Restore original config
+        from ctf.utils import write_config
+        write_config(original_config, str(config_file))