feat: enhance system prompt and tool descriptions to match TS version

Phase 1A implementation:

SystemPromptBuilder.java (142 lines -> ~290 lines):
- Add CyberRisk security boundary instruction
- Add System section (permission modes, prompt injection defense)
- Add Doing Tasks section (coding style, security, collaboration)
- Add Actions section (operation risk management, dangerous ops protection)
- Add Tone & Style section (emoji control, concise output, code references)
- Add Output Efficiency section (direct communication)
- Add Language preference support
- Restructure into modular section builder methods matching TS architecture

Tool description enhancements (8 tools):
- BashTool: add security boundaries, git best practices, no-substitute rule
- FileWriteTool: add must-Read-first rule, prefer-Edit guidance
- GrepTool: add never-use-Bash-grep rule, search guidance
- AgentTool: add when-to-use/not-use guidance, sub-prompt enhanced
- FileEditTool: add indentation preservation, prefer-edit-existing rule
- TodoWriteTool: add proactive usage guidance, state machine rules
- TaskUpdateTool: add status workflow documentation
- ConfigTool: add available settings list

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

src/main/java/com/claudecode/tool/impl/GrepTool.java

@@ -29,8 +29,18 @@ public class GrepTool implements Tool {
     @Override
     public String description() {
         return """
-            Search for a pattern in file contents using regex. Returns matching lines with \
-            file paths and line numbers. Uses ripgrep (rg) if available, falls back to grep.""";
+            A powerful search tool built on ripgrep. Searches for a regex pattern in file contents \
+            and returns matching lines with file paths and line numbers.
+
+            IMPORTANT: ALWAYS use this Grep tool for searching file content. NEVER invoke `grep`, \
+            `rg`, or `findstr` as a Bash command — using this dedicated tool allows the user to \
+            better understand and review your searches.
+
+            Uses ripgrep (rg) if available, falls back to system grep/findstr. Supports full regex \
+            syntax. Use the 'include' parameter to filter by file type (e.g., '*.java', '*.ts').
+
+            When you are doing an open-ended search that may require multiple rounds of searching, \
+            consider using the Agent tool instead to keep the main context clean.""";
     }
 
     @Override