Add Search tool for regex content search

Implements a new Search tool matching Claude Code's interface with:
- pattern (required): regex pattern to search for
- path: directory to search recursively (default: project root)
- output_mode: files_with_matches, content, or count
- glob: filter files by pattern (e.g., "*.rs")
- case_insensitive: case-insensitive matching
- context_before/after: lines of context (content mode)
- max_results: limit results (default: 100)

Includes 10 unit tests covering all functionality.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: jgarzik

Cargo.lock

@@ -28,3 +28,6 @@ uuid = { version = "1", features = ["v4"] }
 wait-timeout = "0.2"
 walkdir = "2"
 shell-words = "1.1"
+
+[dev-dependencies]
+tempfile = "3"

Cargo.toml

@@ -30,7 +30,7 @@ impl ToolCategory {
     /// Determine the category of a tool by name
     pub fn from_tool_name(name: &str) -> Self {
         match name {
-            "Read" | "Grep" | "Glob" => ToolCategory::ReadOnly,
+            "Read" | "Grep" | "Glob" | "Search" => ToolCategory::ReadOnly,
             "Write" | "Edit" => ToolCategory::Mutation,
             "Bash" => ToolCategory::Execution,
             _ if name.starts_with("mcp.") => ToolCategory::Execution, // MCP tools require permission
@@ -82,7 +82,7 @@ impl PolicyEngine {
     /// Extract the primary argument for rule matching from tool args
     /// For Bash: the command string
     /// For Write/Edit/Read: the path
-    /// For Grep/Glob: the pattern
+    /// For Grep/Glob/Search: the pattern
     fn extract_tool_arg(tool: &str, args: &Value) -> Option<String> {
         match tool {
             "Bash" => args
@@ -92,7 +92,7 @@ impl PolicyEngine {
             "Write" | "Edit" | "Read" => {
                 args.get("path").and_then(|v| v.as_str()).map(String::from)
             }
-            "Grep" | "Glob" => args
+            "Grep" | "Glob" | "Search" => args
                 .get("pattern")
                 .and_then(|v| v.as_str())
                 .map(String::from),

src/policy.rs

@@ -5,6 +5,7 @@ mod glob;
 mod grep;
 pub mod mcp_dispatch;
 mod read;
+mod search;
 pub mod task;
 mod write;
 
@@ -34,6 +35,7 @@ pub fn schemas(opts: &SchemaOptions) -> Vec<Value> {
         edit::schema(opts),
         grep::schema(opts),
         glob::schema(opts),
+        search::schema(opts),
         bash::schema(opts),
     ]
 }
@@ -46,6 +48,7 @@ pub fn schemas_with_task(opts: &SchemaOptions) -> Vec<Value> {
         edit::schema(opts),
         grep::schema(opts),
         glob::schema(opts),
+        search::schema(opts),
         bash::schema(opts),
         task::schema(opts),
         activate_skill::schema(opts),
@@ -61,6 +64,7 @@ pub fn execute(name: &str, args: Value, root: &Path, bash_config: &BashConfig) -
         "Edit" => edit::execute(args, root),
         "Grep" => grep::execute(args, root),
         "Glob" => glob::execute(args, root),
+        "Search" => search::execute(args, root),
         "Bash" => bash::execute(args, root, bash_config),
         _ => Ok(
             json!({ "error": { "code": "unknown_tool", "message": format!("Unknown tool: {}", name) } }),