[LLDB] Add SBProgress so Python scripts can also report progress (#119052)

Recently I've been working on a lot of internal Python tooling, and in
certain cases I want to report async to the script over DAP. Progress.h
already handles this, so I've exposed Progress via the SB API so Python
scripts can also update progress objects.

I actually have no idea how to test this, so I just wrote a [toy command
to test
it](https://gist.github.com/Jlalond/48d85e75a91f7a137e3142e6a13d0947)


![image](https://github.com/user-attachments/assets/7317cbb8-9145-4fdb-bacf-9864bf50c467)

I also copied the first section of the extensive Progress.h class
documentation to the docstrings.

1 files changed, 35 insertions, 0 deletions

diff --git a/lldb/test/API/python_api/sbprogress/TestSBProgress.py b/lldb/test/API/python_api/sbprogress/TestSBProgress.py
new file mode 100644
index 0000000..c456247
--- /dev/null
+++ b/lldb/test/API/python_api/sbprogress/TestSBProgress.py
@@ -0,0 +1,35 @@
+"""Test the SBProgress API."""
+
+import lldb
+from lldbsuite.test.lldbtest import *
+
+
+class SBProgressTestCase(TestBase):
+    def test_with_external_bit_set(self):
+        """Test SBProgress events are listened to when the external bit is set."""
+
+        progress = lldb.SBProgress("Test SBProgress", "Test progress", self.dbg)
+        listener = lldb.SBListener("Test listener")
+        broadcaster = self.dbg.GetBroadcaster()
+        broadcaster.AddListener(listener, lldb.eBroadcastBitExternalProgress)
+        event = lldb.SBEvent()
+
+        expected_string = "Test progress first increment"
+        progress.Increment(1, expected_string)
+        self.assertTrue(listener.PeekAtNextEvent(event))
+        stream = lldb.SBStream()
+        event.GetDescription(stream)
+        self.assertIn(expected_string, stream.GetData())
+
+    def test_without_external_bit_set(self):
+        """Test SBProgress events are not listened to on the internal progress bit."""
+
+        progress = lldb.SBProgress("Test SBProgress", "Test progress", self.dbg)
+        listener = lldb.SBListener("Test listener")
+        broadcaster = self.dbg.GetBroadcaster()
+        broadcaster.AddListener(listener, lldb.eBroadcastBitProgress)
+        event = lldb.SBEvent()
+
+        expected_string = "Test progress first increment"
+        progress.Increment(1, expected_string)
+        self.assertFalse(listener.PeekAtNextEvent(event))