refactor: refactor RTL paths and update test descriptions

- Updated RTL paths in various files to remove the 'ribp' prefix, reflecting the new directory structure.
- Modified test descriptions to remove version indicators (e.g., V2, V3) for clarity and consistency.
- Adjusted file references in scripts and tests to align with the new peripheral and multimedia directory structure.
- Added a new test to ensure repository layout invariants, confirming the absence of deprecated paths.

tests/test_repository_layout.py

@@ -0,0 +1,32 @@
+"""Repository layout invariants for self-owned IP and dependency inputs."""
+
+from pathlib import Path
+
+
+ROOT = Path(__file__).resolve().parents[1]
+
+
+def test_self_owned_ip_is_flattened_and_dependency_lock_is_distinct() -> None:
+    assert not (ROOT / "rtl/ip/ribp").exists()
+    assert (ROOT / "rtl/ip/peripheral").is_dir()
+    assert (ROOT / "rtl/ip/serial").is_dir()
+    assert not (ROOT / "config").exists()
+    assert (ROOT / "dependencies/dependencies.lock.json").is_file()
+    assert (ROOT / "configs/ci/ihp130.mk").is_file()
+
+
+def test_active_sources_do_not_reference_removed_paths() -> None:
+    roots = (ROOT / "rtl/mini", ROOT / "scripts", ROOT / "tests", ROOT / "docs")
+    removed_ip_path = "rtl/ip/" + "ribp"
+    removed_filelist_path = "/ip/" + "ribp"
+    removed_lock_path = "config/" + "dependencies.lock.json"
+    for search_root in roots:
+        for path in search_root.rglob("*"):
+            if path == Path(__file__):
+                continue
+            if not path.is_file() or path.suffix not in {".fl", ".mk", ".json", ".md", ".py"}:
+                continue
+            text = path.read_text(encoding="utf-8")
+            assert removed_ip_path not in text
+            assert removed_filelist_path not in text
+            assert removed_lock_path not in text