Use native VSCode coverage APIs, cover swift-testing

Move to the new VSCode coverage APIs that were introduced in VSCode
version 1.88. This allows us to remove the coverage renderer and
coverage report files. This functionality is now built in to the test
explorer and VSCode's document rendering.

This patch also adds support for producing test coverage from
swift-testing tests. XCTests and swift-testing tests are each run in
their respective binaries and then the coverage data is merged into a
profdata file before being exported to LCOV format.

Finally we transform the LCOV JSON into the coverage structures for
VSCode and associate this data with the test run.

Author: plemarquand

package-lock.json

@@ -10,7 +10,7 @@
     "url": "https://github.com/swift-server/vscode-swift"
   },
   "engines": {
-    "vscode": "^1.71.0"
+    "vscode": "^1.88.0"
   },
   "categories": [
     "Programming Languages",
@@ -447,47 +447,6 @@
           }
         }
       },
-      {
-        "title": "Test Coverage",
-        "properties": {
-          "swift.coverage.displayReportAfterRun": {
-            "type": "boolean",
-            "default": true,
-            "description": "Should test coverage report be shown after running tests",
-            "order": 1
-          },
-          "swift.coverage.alwaysShowStatusItem": {
-            "type": "boolean",
-            "default": true,
-            "description": "Always show the test coverage status item. If this is set to true the status item can be clicked on to toggle test coverage display on and off.",
-            "order": 2
-          },
-          "swift.coverage.colors.lightMode.hit": {
-            "type": "string",
-            "default": "#c0ffc0",
-            "description": "Light mode theme background color for line of code hit during test coverage.",
-            "order": 3
-          },
-          "swift.coverage.colors.lightMode.miss": {
-            "type": "string",
-            "default": "#ffc0c0",
-            "description": "Light mode theme background color for line of code missed during test coverage.",
-            "order": 4
-          },
-          "swift.coverage.colors.darkMode.hit": {
-            "type": "string",
-            "default": "#003000",
-            "description": "Dark mode theme background color for line of code hit during test coverage.",
-            "order": 5
-          },
-          "swift.coverage.colors.darkMode.miss": {
-            "type": "string",
-            "default": "#400000",
-            "description": "Dark mode theme background color for line of code missed during test coverage.",
-            "order": 6
-          }
-        }
-      },
       {
         "title": "Debugger",
         "properties": {
@@ -1170,7 +1129,7 @@
     "@types/mocha": "^10.0.1",
     "@types/node": "^18.19.33",
     "@types/plist": "^3.0.5",
-    "@types/vscode": "^1.71.0",
+    "@types/vscode": "^1.88.0",
     "@typescript-eslint/eslint-plugin": "^7.8.0",
     "@typescript-eslint/parser": "^7.8.0",
     "@vscode/test-electron": "^2.3.8",