v0.4.0

Added

• Highlight the users' messages in the chat section: Now the chat sections highlights and spots the users' mesagges in blocks
  for a easely reading of the chat
• Rich text support in the TUI chat renderer: Added rich text rendering support for chat output in the terminal UI.
• Project-local skills system: RubyCoded can now load Markdown skill files from .rubycoded/skills/ using YAML frontmatter metadata (name, description, modes, optional tags, trigger, and priority) and expose them as reusable project instructions.
• Skill management commands: Added /skills reload and /skills list to reload and inspect project-local skills without restarting the application.
• Skill validation and cataloging: Added a dedicated RubyCoded::Skills subsystem with a markdown loader, normalized skill definitions, duplicate detection, invalid file reporting, and mode-aware in-memory cataloging.

Changed

• Refactor chat panel rendering system into multiple modules
• Prompt construction now supports project skills: Chat, plan, and agent mode instructions now append relevant project-local skills so project-specific guidance is consistently available across runtime modes, including Codex-backed sessions.
• Ruby-conventional predicate names on bridges: LLMBridge and CodexBridge now expose agentic_mode? and plan_mode? (previously agentic_mode / plan_mode). Plugins that read these predicates need to update the call site.
• Internal chat bridge refactor: Extracted RuntimeMode as the single source of truth for chat/agent/plan modes, BridgeFactory for backend selection, Tools::ExecutionPolicy for centralized risk/approval/limits, PromptBuilder for mode-aware system instructions, and BridgeCommon (ModeTransitions, ToolFlow, AutoSwitch) to share behavior between LLMBridge and CodexBridge.
• Tool execution pipeline: Added Tools::ExecutionPipeline and BaseTool#run_pipeline to standardize path validation, project-root guarding and filesystem error normalization for side-effecting tools; adopted in WriteFileTool, EditFileTool and DeletePathTool.
• Extension model documented: The README now describes the boundary between commands, skills and plugins.