feat(core): implement Glob and Grep search tools

- Add GlobTool for finding files matching glob patterns
  - Supports ** recursive patterns
  - Configurable max results (default 1000)
  - Base directory support

- Add GrepTool for searching file contents with regex
  - Regex pattern matching
  - Case insensitive option
  - File glob filtering
  - Directory recursive search
  - Max matches limit (default 100)

- Add glob and regex dependencies to workspace
- Export GlobTool and GrepTool from lib.rs
- Update create_file_tool_registry (5 tools)
- Update create_standard_tool_registry (6 tools)
- Add 7 tests for Glob and Grep tools

Closes #27

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

Cargo.toml

@@ -61,3 +61,5 @@ reqwest = { version = "0.12", features = ["json", "stream"] }
 chrono = { version = "0.4", features = ["serde"] }
 uuid = { version = "1", features = ["v4", "serde"] }
 once_cell = "1"
+glob = "0.3"
+regex = "1"