feat: add pysubs2 subtitle conversion with extended format support

- Add pysubs2 as default conversion method for 'auto' mode
- Add support for MicroDVD (.sub), MPL2 (.mpl2), and TMP (.tmp) formats
- Implement convert_with_pysubs2() method with fallback to standard conversion
- Update from_mime() to handle new subtitle format types
- Map all supported formats to pysubs2 format identifiers
- Update docstrings to reflect new capabilities

uv.lock

@@ -1174,6 +1174,15 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/8d/59/b4572118e098ac8e46e399a1dd0f2d85403ce8bbaad9ec79373ed6badaf9/PySocks-1.7.1-py3-none-any.whl", hash = "sha256:2725bd0a9925919b9b51739eea5f9e2bae91e83288108a9ad338b2e3a4435ee5", size = 16725, upload-time = "2019-09-20T02:06:22.938Z" },
 ]
 
+[[package]]
+name = "pysubs2"
+version = "1.8.0"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/31/4a/becf78d9d3df56e6c4a9c50b83794e5436b6c5ab6dd8a3f934e94c89338c/pysubs2-1.8.0.tar.gz", hash = "sha256:3397bb58a4a15b1325ba2ae3fd4d7c214e2c0ddb9f33190d6280d783bb433b20", size = 1130048, upload-time = "2024-12-24T12:39:47.769Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/99/09/0fc0719162e5ad723f71d41cf336f18b6b5054d70dc0fe42ace6b4d2bdc9/pysubs2-1.8.0-py3-none-any.whl", hash = "sha256:05716f5039a9ebe32cd4d7673f923cf36204f3a3e99987f823ab83610b7035a0", size = 43516, upload-time = "2024-12-24T12:39:44.469Z" },
+]
+
 [[package]]
 name = "pywidevine"
 version = "1.8.0"
@@ -1523,6 +1532,7 @@ dependencies = [
     { name = "pymp4" },
     { name = "pymysql" },
     { name = "pyplayready" },
+    { name = "pysubs2" },
     { name = "pywidevine", extra = ["serve"] },
     { name = "pyyaml" },
     { name = "requests", extra = ["socks"] },
@@ -1562,7 +1572,7 @@ requires-dist = [
     { name = "httpx", specifier = ">=0.28.1,<0.29" },
     { name = "jsonpickle", specifier = ">=3.0.4,<4" },
     { name = "langcodes", specifier = ">=3.4.0,<4" },
-    { name = "lxml", specifier = ">=5.2.1,<6" },
+    { name = "lxml", specifier = ">=5.2.1,<7" },
     { name = "pproxy", specifier = ">=2.7.9,<3" },
     { name = "protobuf", specifier = ">=4.25.3,<5" },
     { name = "pycaption", specifier = ">=2.2.6,<3" },
@@ -1572,6 +1582,7 @@ requires-dist = [
     { name = "pymp4", specifier = ">=1.4.0,<2" },
     { name = "pymysql", specifier = ">=1.1.0,<2" },
     { name = "pyplayready", specifier = ">=0.6.0,<0.7" },
+    { name = "pysubs2", specifier = ">=1.7.0,<2" },
     { name = "pywidevine", extras = ["serve"], specifier = ">=1.8.0,<2" },
     { name = "pyyaml", specifier = ">=6.0.1,<7" },
     { name = "requests", extras = ["socks"], specifier = ">=2.31.0,<3" },