Add integration tests for inofity limits

inotify exposes a /proc interface to limit kernel memory usage. If those
limits are set too low, inotify cannot add all watches. The integration
test verifies, that Inotify yields an error in that case.

Tests/InotifyIntegrationTests/InotifyLimitTests.swift

@@ -0,0 +1,43 @@
+import Testing
+import Foundation
+@testable import Inotify
+
+@Suite("Inotify Limits", .serialized)
+struct InotifyLimitTests {
+	@Test func throwsIfInotifyUpperLimitReached() async throws {
+		try await withTempDir { dir in
+			try await withInotifyWatchLimit(of: 10) {
+				try createSubdirectorytree(at: dir, foldersPerLevel: 4, levels: 3)
+				try await Task.sleep(for: .milliseconds(100))
+
+				await #expect(throws: InotifyError.self) {
+					let watcher = try Inotify()
+					try await watcher.addRecursiveWatch(forDirectory: dir, mask: .allEvents)
+				}
+			}
+		}
+	}
+
+	@Test func watchesMassivSubtreesIfAllowed() async throws {
+		try await withTempDir { dir in
+			try await withInotifyWatchLimit(of: 1000) {
+				try createSubdirectorytree(at: dir, foldersPerLevel: 8, levels: 3)
+				let subDirectory = "\(dir)/Folder 8/Folder 8/Folder 8"
+				let filepath = "\(subDirectory)/new-file.txt"
+				try await Task.sleep(for: .milliseconds(100))
+
+				let events = try await getEventsForTrigger(
+					in: dir,
+					mask: [.create],
+					recursive: .recursive
+				) { _ in
+					assert(FileManager.default.fileExists(atPath: subDirectory))
+					try createFile(at: "\(filepath)", contents: "hello")
+				}
+
+				let createEvent = events.first { $0.mask.contains(.create) && $0.path.string == filepath }
+				#expect(createEvent != nil, "Expected CREATE for '\(filepath)', got: \(events)")
+			}
+		}
+	}
+}