River : HLE: Make process identity explicit for service metadata resolution (#100)

This PR is the first in a batch of structural changes to Ryujinx.

**Changes**

- Added `ProcessIdentity` and `ProcessKind` to describe loaded programs by:
  - PID, program ID, application ID, program index, display version, process kind
- Stored identity metadata on `ProcessResult`.
- Added PID-based process lookup helpers to `ProcessLoader`.
- Updated HLE services to resolve application metadata through the caller PID instead of `Processes.ActiveApplication`.
- Added PTC/JIT disk cache initialization logging with PID, title ID, display version, selector, and enabled state.
- Added `ClientProcessId` property to ServiceCtx (/src/Ryujinx.HLE/HOS/ServiceCtx.cs) that uses the handle descriptor PId when available, falling back to `Process.Pid`.
- Updated 15 HLE service files to use `context.ClientProcessId` instead of `context.Process.Pid` for client process access, ensuring services correctly identify the calling process even when invoked via IPC with handle descriptors.

These changes make service metadata resolution more explicit and prepare the emulator for other structural changes later on.

Reviewed-on: https://git.ryujinx.app/projects/Ryubing/pulls/100

src/Ryujinx.HLE/Loaders/Processes/ProcessLoader.cs

@@ -93,6 +93,23 @@ namespace Ryujinx.HLE.Loaders.Processes
             _processesByPid = new ConcurrentDictionary<ulong, ProcessResult>();
         }
 
+        public bool TryGetProcess(ulong pid, out ProcessResult process)
+        {
+            return _processesByPid.TryGetValue(pid, out process);
+        }
+
+        public ProcessResult GetProcess(ulong pid)
+        {
+            if (_processesByPid.TryGetValue(pid, out ProcessResult process))
+            {
+                return process;
+            }
+
+            Logger.Warning?.Print(LogClass.Loader, $"Process metadata for pid {pid} was not found. Falling back to active application metadata.");
+
+            return ActiveApplication;
+        }
+
         public bool LoadXci(string path, ulong applicationId)
         {
             FileStream stream = new(path, FileMode.Open, FileAccess.Read);