feat: replace inotify watch path with fsnotify and clean up related tooling/docs (#204)

* Plan fsnotify migration and docs updates

Co-authored-by: Belphemur <197810+Belphemur@users.noreply.github.com>

* Refactor watch mode to fsnotify and add agent docs

Co-authored-by: Belphemur <197810+Belphemur@users.noreply.github.com>

* Fix errcheck violations in command and converter tests

Co-authored-by: Belphemur <197810+Belphemur@users.noreply.github.com>

* Complete validation for fsnotify and lint fixes

Co-authored-by: Belphemur <197810+Belphemur@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Belphemur <197810+Belphemur@users.noreply.github.com>

AGENTS.md

@@ -0,0 +1,22 @@
+# Agent Instructions
+
+This repository contains AI-agent oriented project context.
+
+## Read first
+
+- `docs/project-overview.md` for architecture and execution flow.
+- `docs/development.md` for build/test/lint commands and runtime prerequisites.
+
+## Repository conventions
+
+- Language: Go
+- CLI framework: Cobra + Viper
+- Logging: zerolog
+- Error wrapping: `fmt.Errorf("context: %w", err)`
+- Prefer small, focused changes.
+
+## Areas to know
+
+- Watch command: `cmd/cbzoptimizer/commands/watch_command.go`
+- Optimization orchestration: `internal/utils/optimize.go`
+- Converter interface/impl: `pkg/converter/`