Add unit tests, integration test, CI workflow, and conventions

- gitea/client_test.go: mock HTTP tests for all API methods + error cases
- llm/client_test.go: mock tests for completion, errors, timeouts
- review/parser_test.go: JSON parsing, markdown fences, validation
- review/formatter_test.go: markdown output, empty/multiple findings
- review/prompt_test.go: system/user prompt construction
- integration_test.go: full end-to-end flow (build tag: integration)
- .gitea/workflows/ci.yml: test + vet + build on push, dual LLM review on PRs
- CONVENTIONS.md: coding standards for self-review dogfooding
- README.md: usage docs, env vars, architecture

review/prompt_test.go

@@ -0,0 +1,77 @@
+package review
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestBuildSystemPrompt_NoConventions(t *testing.T) {
+	prompt := BuildSystemPrompt("")
+
+	if !strings.Contains(prompt, "expert code reviewer") {
+		t.Error("expected system prompt to mention code reviewer role")
+	}
+	if strings.Contains(prompt, "coding conventions") {
+		t.Error("should not mention conventions when empty")
+	}
+}
+
+func TestBuildSystemPrompt_WithConventions(t *testing.T) {
+	conventions := "- Use stdlib only\n- No panics\n"
+	prompt := BuildSystemPrompt(conventions)
+
+	if !strings.Contains(prompt, "coding conventions") {
+		t.Error("expected conventions section")
+	}
+	if !strings.Contains(prompt, "Use stdlib only") {
+		t.Error("expected conventions content")
+	}
+}
+
+func TestBuildUserPrompt_Basic(t *testing.T) {
+	prompt := BuildUserPrompt("Fix bug", "Fixes the crash", "diff content here", true, "all checks passed")
+
+	if !strings.Contains(prompt, "Fix bug") {
+		t.Error("expected PR title")
+	}
+	if !strings.Contains(prompt, "Fixes the crash") {
+		t.Error("expected PR description")
+	}
+	if !strings.Contains(prompt, "diff content here") {
+		t.Error("expected diff content")
+	}
+	if !strings.Contains(prompt, "PASSED") {
+		t.Error("expected CI status PASSED")
+	}
+}
+
+func TestBuildUserPrompt_CIFailed(t *testing.T) {
+	prompt := BuildUserPrompt("Add tests", "", "some diff", false, "lint: failed")
+
+	if !strings.Contains(prompt, "FAILED") {
+		t.Error("expected CI status FAILED")
+	}
+	if !strings.Contains(prompt, "lint: failed") {
+		t.Error("expected CI details")
+	}
+}
+
+func TestBuildUserPrompt_NoDescription(t *testing.T) {
+	prompt := BuildUserPrompt("Quick fix", "", "diff", true, "")
+
+	if strings.Contains(prompt, "### Description") {
+		t.Error("should not contain Description header when body is empty")
+	}
+}
+
+func TestBuildUserPrompt_DiffIncluded(t *testing.T) {
+	diff := "+func Hello() string {\n+\treturn \"hello\"\n+}"
+	prompt := BuildUserPrompt("Greeting", "Add greeting func", diff, true, "")
+
+	if !strings.Contains(prompt, "```diff") {
+		t.Error("expected diff fence")
+	}
+	if !strings.Contains(prompt, diff) {
+		t.Error("expected diff content in prompt")
+	}
+}