Add first set of unit-tests in Bazel

.bazelrc

@@ -1 +1,2 @@
 common --experimental_enable_bzlmod
+build --incompatible_default_to_explicit_init_py=true

tests_unit/BUILD

@@ -0,0 +1,54 @@
+test_suite(
+    name = "tests_unit",
+    tests = [
+        ":test_file_tag_generator",
+        ":test_io",
+        ":test_io_signal_duplicate_items",
+        ":test_items",
+        ":test_location",
+        ":test_meta_data_tool_base",
+        ":test_tool",
+    ],
+)
+
+py_test(
+    name = "test_file_tag_generator",
+    srcs = ["test_file_tag_generator.py"],
+    deps = ["//:lobster"],
+)
+
+py_test(
+    name = "test_io",
+    srcs = ["test_io.py"],
+    deps = ["//:lobster"],
+)
+
+py_test(
+    name = "test_io_signal_duplicate_items",
+    srcs = ["test_io_signal_duplicate_items.py"],
+    deps = ["//:lobster"],
+)
+
+py_test(
+    name = "test_items",
+    srcs = ["test_items.py"],
+    deps = ["//:lobster"],
+)
+
+py_test(
+    name = "test_location",
+    srcs = ["test_location.py"],
+    deps = ["//:lobster"],
+)
+
+py_test(
+    name = "test_meta_data_tool_base",
+    srcs = ["test_meta_data_tool_base.py"],
+    deps = ["//:lobster"],
+)
+
+py_test(
+    name = "test_tool",
+    srcs = ["test_tool.py"],
+    deps = ["//:lobster"],
+)