feat(tools): issue_get, release_create, repo_delete (#11, #17, #20)

issue_get: GET /repos/{owner}/{repo}/issues/{number} — full issue with labels, assignees, comment count
release_create: POST /repos/{owner}/{repo}/releases — create release and tag in one call
repo_delete: DELETE /repos/{owner}/{repo} — confirm=<repo name> required, blocks accidents

internal/tools/repo_delete_test.go

@@ -0,0 +1,52 @@
+package tools_test
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/allowlist"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/gitea"
+	"gitea.d-ma.be/mathias/gitea-mcp/internal/tools"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestRepoDeleteTool_WithCorrectConfirm(t *testing.T) {
+	deleted := false
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		assert.Equal(t, http.MethodDelete, r.Method)
+		assert.Equal(t, "/api/v1/repos/mathias/infra", r.URL.Path)
+		deleted = true
+		w.WriteHeader(http.StatusNoContent)
+	}))
+	defer srv.Close()
+
+	tool := tools.NewRepoDelete(gitea.NewClient(srv.URL, "tok"), allowlist.New([]string{"mathias"}))
+	out, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"mathias","name":"infra","confirm":"infra"}`))
+	require.NoError(t, err)
+	assert.True(t, deleted, "DELETE request must have been sent")
+	assert.Contains(t, string(out), "deleted")
+}
+
+func TestRepoDeleteTool_WrongConfirmBlocked(t *testing.T) {
+	tool := tools.NewRepoDelete(gitea.NewClient("http://unused", ""), allowlist.New([]string{"mathias"}))
+	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"mathias","name":"infra","confirm":"wrong"}`))
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "confirm")
+}
+
+func TestRepoDeleteTool_MissingConfirmBlocked(t *testing.T) {
+	tool := tools.NewRepoDelete(gitea.NewClient("http://unused", ""), allowlist.New([]string{"mathias"}))
+	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"mathias","name":"infra"}`))
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "confirm")
+}
+
+func TestRepoDeleteAllowlistRejects(t *testing.T) {
+	tool := tools.NewRepoDelete(gitea.NewClient("http://unused", ""), allowlist.New([]string{"mathias"}))
+	_, err := tool.Call(context.Background(), json.RawMessage(`{"owner":"evil","name":"x","confirm":"x"}`))
+	require.Error(t, err)
+}