refactor: restructure codebase to internal/ directory with modular architecture

- Move all source files to internal/{app,backend,config,executor,logger,parser,utils}
- Integrate third-party libraries: zerolog, goccy/go-json, gopsutil, cobra/viper
- Add comprehensive unit tests for utils package (94.3% coverage)
- Add performance benchmarks for string operations
- Fix error display: cleanup warnings no longer pollute Recent Errors
- Add GitHub Actions CI workflow
- Add Makefile for build automation
- Add README documentation

Generated with SWE-Agent.ai

Co-Authored-By: SWE-Agent.ai <noreply@swe-agent.ai>

codeagent-wrapper/Makefile

@@ -0,0 +1,38 @@
+GO ?= go
+
+BINARY ?= codeagent
+CMD_PKG := ./cmd/codeagent
+
+TOOLS_BIN := $(CURDIR)/bin
+TOOLCHAIN ?= go1.22.0
+GOLANGCI_LINT_VERSION := v1.56.2
+STATICCHECK_VERSION := v0.4.7
+
+GOLANGCI_LINT := $(TOOLS_BIN)/golangci-lint
+STATICCHECK := $(TOOLS_BIN)/staticcheck
+
+.PHONY: build test lint clean install
+
+build:
+	$(GO) build -o $(BINARY) $(CMD_PKG)
+
+test:
+	$(GO) test ./...
+
+$(GOLANGCI_LINT):
+	@mkdir -p $(TOOLS_BIN)
+	GOTOOLCHAIN=$(TOOLCHAIN) GOBIN=$(TOOLS_BIN) $(GO) install github.com/golangci/golangci-lint/cmd/golangci-lint@$(GOLANGCI_LINT_VERSION)
+
+$(STATICCHECK):
+	@mkdir -p $(TOOLS_BIN)
+	GOTOOLCHAIN=$(TOOLCHAIN) GOBIN=$(TOOLS_BIN) $(GO) install honnef.co/go/tools/cmd/staticcheck@$(STATICCHECK_VERSION)
+
+lint: $(GOLANGCI_LINT) $(STATICCHECK)
+	GOTOOLCHAIN=$(TOOLCHAIN) $(GOLANGCI_LINT) run ./...
+	GOTOOLCHAIN=$(TOOLCHAIN) $(STATICCHECK) ./...
+
+clean:
+	@python3 -c 'import glob, os; paths=["codeagent","codeagent.exe","codeagent-wrapper","codeagent-wrapper.exe","coverage.out","cover.out","coverage.html"]; paths += glob.glob("coverage*.out") + glob.glob("cover_*.out") + glob.glob("*.test"); [os.remove(p) for p in paths if os.path.exists(p)]'
+
+install:
+	$(GO) install $(CMD_PKG)