feat: implement versioning and release management in the project

- Added automatic versioning based on git tags using semantic-release in Gitea Actions.
- Introduced new API endpoints `GET /version` and `GET /v1/version` to expose build metadata.
- Updated Docker build process to include version and build time information in Go binaries.
- Enhanced documentation with details on release processes and versioning guidelines.
- Integrated version display in the web application for better user visibility.

internal/httpapi/routes.go

@@ -21,6 +21,7 @@ import (
 	"evobgp/internal/pipeline"
 	"evobgp/internal/reports"
 	"evobgp/internal/store"
+	"evobgp/internal/version"
 )
 
 // Handler returns the root HTTP handler (system routes public; rest under /v1/ authenticated).
@@ -30,6 +31,7 @@ func (s *Server) Handler() http.Handler {
 	wrappedV1 := http.StripPrefix("/v1", v1)
 
 	s.mux.Handle("GET /metrics", observability.MetricsHandler())
+	s.mux.HandleFunc("GET /version", s.handleVersion)
 	s.mux.HandleFunc("GET /v1/health", s.handleHealth)
 	s.mux.HandleFunc("GET /v1/ready", s.handleReady)
 	s.mux.HandleFunc("GET /v1/version", s.handleVersion)
@@ -96,11 +98,16 @@ func (s *Server) handleReady(w http.ResponseWriter, r *http.Request) {
 }
 
 func (s *Server) handleVersion(w http.ResponseWriter, r *http.Request) {
-	sha := strings.TrimSpace(os.Getenv("EVOBGP_GIT_SHA"))
-	if sha == "" {
-		sha = "unknown"
+	ver, sha, buildTime := version.Info()
+	resp := map[string]string{
+		"version":     ver,
+		"api_version": ver,
+		"git_sha":     sha,
 	}
-	writeJSON(w, http.StatusOK, map[string]string{"api_version": "0.1.0", "git_sha": sha})
+	if buildTime != "" {
+		resp["build_time"] = buildTime
+	}
+	writeJSON(w, http.StatusOK, resp)
 }
 
 func moduleJSON(mod *store.Module) map[string]any {

internal/httpapi/server_test.go

@@ -13,6 +13,7 @@ import (
 
 	"evobgp/internal/jobs"
 	"evobgp/internal/signing"
+	"evobgp/internal/version"
 )
 
 const testBundleSeed = "0101010101010101010101010101010101010101010101010101010101010101"
@@ -371,3 +372,60 @@ evobgp_p_01234567 BGP      master  start 2026-04-09  Connect
 		t.Fatalf("expected protocol state Connect, got %q", got["evobgp_p_01234567"])
 	}
 }
+
+func TestVersionEndpoints(t *testing.T) {
+	srv, err := New(Options{
+		InsecureDev:   true,
+		SeedDemo:      true,
+		BundleSeedHex: testBundleSeed,
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer srv.Close()
+
+	oldVer := version.Version
+	oldSHA := version.GitSHA
+	oldTime := version.BuildTime
+	version.Version = "1.2.3"
+	version.GitSHA = "abc123def456"
+	version.BuildTime = "2026-05-20T12:00:00Z"
+	t.Cleanup(func() {
+		version.Version = oldVer
+		version.GitSHA = oldSHA
+		version.BuildTime = oldTime
+	})
+
+	ts := httptest.NewServer(srv.Handler())
+	defer ts.Close()
+
+	for _, path := range []string{"/version", "/v1/version"} {
+		t.Run(path, func(t *testing.T) {
+			resp, err := http.Get(ts.URL + path)
+			if err != nil {
+				t.Fatal(err)
+			}
+			defer resp.Body.Close()
+			if resp.StatusCode != http.StatusOK {
+				b, _ := io.ReadAll(resp.Body)
+				t.Fatalf("status %d: %s", resp.StatusCode, b)
+			}
+			var body map[string]string
+			if err := json.NewDecoder(resp.Body).Decode(&body); err != nil {
+				t.Fatal(err)
+			}
+			if body["version"] != "1.2.3" {
+				t.Fatalf("version=%q want 1.2.3", body["version"])
+			}
+			if body["api_version"] != "1.2.3" {
+				t.Fatalf("api_version=%q want 1.2.3", body["api_version"])
+			}
+			if body["git_sha"] != "abc123def456" {
+				t.Fatalf("git_sha=%q", body["git_sha"])
+			}
+			if body["build_time"] != "2026-05-20T12:00:00Z" {
+				t.Fatalf("build_time=%q", body["build_time"])
+			}
+		})
+	}
+}