feat(app): report mutations on stderr and say what --web opens

Mutations printed a list row, or nothing, so a person could not tell
what changed and scripts parsed rows meant for people. Commands now get
the helpers for the gh convention:

- done and warn print "✓ Closed issue alice/x#5 (Fix login)" and
  "! … is already closed" to stderr, only when stdout is a terminal and
  --json is not set.
- printURL prints a created resource's URL to stdout unless --json is
  set, so url=$(tea issue create …) works.
- batchDone applies a mutation to several selections like batch and
  reports each success with a done line instead of a table.
- issueRef formats "alice/x#5 (title)" references.

--web now prints "Opening localhost:3001/alice/project/issues/1 in your
browser." to stderr on a terminal before the browser starts.

Signed-off-by: bircni <bircni@icloud.com>

internal/app/browser_test.go

@@ -68,3 +68,21 @@ func TestDiscussionViewsShareBrowserContract(t *testing.T) {
 		})
 	}
 }
+
+func TestOpenBrowserTellsTerminalUsers(t *testing.T) {
+	for _, tty := range []bool{true, false} {
+		deps, out, diagnostics := testDeps(t)
+		browser := &recordingBrowser{}
+		deps.Browser = browser
+		deps.Streams.OutTTY = tty
+		a, cmd := outputApplication(deps, "")
+		require.NoError(t, a.openBrowser(cmd, "http://localhost:3001/alice/project/issues/1"))
+		require.Equal(t, "http://localhost:3001/alice/project/issues/1", browser.resource)
+		require.Empty(t, out.String())
+		if tty {
+			require.Equal(t, "Opening localhost:3001/alice/project/issues/1 in your browser.\n", diagnostics.String())
+		} else {
+			require.Empty(t, diagnostics.String())
+		}
+	}
+}