Allow Exact Match For Filters

[tthornton3-chwy]

I was having cases where filters were matching inappropriately, for example with composite builds. This lets you have an exact match syntax. I know it's a bit niche, but I do think it's useful/I personally use it!

[tthornton3-chwy]

@microsoft-github-policy-service agree

[chagong]

Thanks, this is a reasonable addition and the trailing-separator approach is backward compatible. One blocker and two smaller asks before merge:

Windows separator gap. The typical config form is !${workspaceFolder}/build/classes/ — after resolution that's an absolute path with forward slashes and a trailing /. Since it's absolute, path.join is skipped, so on Windows exclude.endsWith('\\') is false and exact-match silently never triggers. A Windows user would have to hand-write backslashes. Suggest making the check separator-agnostic and running it before normalization:

if (/[\\/]$/.test(exclude)) {
    exclude = exclude.slice(0, -1);
    isDirect = true;
} else {
    isDirect = this.isFilePath(exclude);
}

Docs. The trailing-slash convention isn't discoverable — can you update java.debugger.launch.classPaths.exclude and modulePaths.exclude in package.nls.json to mention it? It's also slightly counter-intuitive (a trailing slash usually implies a directory/prefix, here it means exact match), so a clear note helps.

Test. A small unit test covering the new exact-match path in filterExcluded would be good given this logic is filesystem-sensitive and currently untested.