fix(csharp): stop tuple-typed properties losing their name to the method branch (#1967)

* fix(csharp): stop tuple-typed properties losing their name to the method branch

_extract_base_name_and_type split Roslyn's "Name : Type" property names by
checking for a literal '(' anywhere in the raw string. A C# tuple type is
written with parentheses ("(int X, string Y)"), so a tuple-typed property
tripped that guard and fell into the method branch instead, which kept the
trailing " :" as part of the reported name (e.g. "Position :"). Since
find_symbol defaults to exact name-path matching, such a property becomes
unfindable by its real name.

The guard now only checks for '(' in the identifier segment before the
first " : ", not the whole string, so a parenthesis inside the type
annotation no longer affects branch selection.

* fix(csharp): bump the high-level symbol cache fingerprint

_normalize_symbol_name's output changed in this PR, and
_document_symbols_cache_fingerprint gates the cache that stores its
result; leaving the version at 1 would keep serving the old, corrupted
names to anyone with an existing on-disk cache.

test/solidlsp/csharp/test_csharp_basic.py

@@ -7,6 +7,7 @@ import pytest
 
 from solidlsp import SolidLanguageServer
 from solidlsp.language_servers.csharp_language_server import (
+    CSharpLanguageServer,
     breadth_first_file_scan,
     find_solution_or_project_file,
 )
@@ -200,6 +201,28 @@ class TestCSharpLanguageServer:
             ), f"Expected ConsoleGreeter.FormatGreeting symbol, got: {implementing_symbols}"
 
 
+class TestCSharpExtractBaseNameAndType:
+    """Regression tests for _extract_base_name_and_type, no running language server needed."""
+
+    @pytest.mark.parametrize(
+        ("roslyn_name", "expected"),
+        [
+            # Property whose type is a tuple: the literal '(' in the type must not be
+            # mistaken for a method's parameter list.
+            ("Position : (int X, string Y)", ("Position", ": (int X, string Y)")),
+            ("Name : string", ("Name", ": string")),
+            ("Add(int, int) : int", ("Add", "(int, int) : int")),
+            ("ToString()", ("ToString", "()")),
+            ("SimpleMethod", ("SimpleMethod", "")),
+            # Both still have a '(' before the first " : ", so they keep the method branch.
+            ("GetPair() : (int, int)", ("GetPair", "() : (int, int)")),
+            ("Merge((int, int) a, (int, int) b) : void", ("Merge", "((int, int) a, (int, int) b) : void")),
+        ],
+    )
+    def test_extract_base_name_and_type(self, roslyn_name: str, expected: tuple[str, str]) -> None:
+        assert CSharpLanguageServer._extract_base_name_and_type(roslyn_name) == expected
+
+
 @pytest.mark.csharp
 class TestCSharpSolutionProjectOpening:
     """Test C# language server solution and project opening functionality."""