fix: include finish milestones (TT_FinMile) in milestone queries

The list_milestones tool was only returning start milestones (TT_Mile)
and missing all finish milestones. P6 uses two task types for milestones:
- TT_Mile = Start Milestone
- TT_FinMile = Finish Milestone

Changes:
- Update query_milestones() to include both TT_Mile and TT_FinMile
- Derive milestone_type from task_type when not explicitly set:
  - TT_Mile -> 'start'
  - TT_FinMile -> 'finish'
- Add unit tests for milestone_type derivation from task_type

This fixes the E-J Electric schedule returning 5 milestones instead of 62.

tests/unit/test_table_handlers.py

@@ -157,6 +157,147 @@ class TestTaskHandler:
         assert result["early_start_date"] is None
         assert result["early_end_date"] is None
 
+    def test_parse_milestone_type_start(self) -> None:
+        """Handler should parse milestone_type='start' for start milestones."""
+        from xer_mcp.parser.table_handlers.task import TaskHandler
+
+        handler = TaskHandler()
+
+        fields = [
+            "task_id",
+            "proj_id",
+            "task_code",
+            "task_name",
+            "task_type",
+            "milestone_type",
+        ]
+        values = [
+            "2001",
+            "1001",
+            "MS-START",
+            "Project Start",
+            "TT_Mile",
+            "MS_Start",
+        ]
+
+        result = handler.parse_row(fields, values)
+
+        assert result is not None
+        assert result["task_type"] == "TT_Mile"
+        assert result["milestone_type"] == "start"
+
+    def test_parse_milestone_type_finish(self) -> None:
+        """Handler should parse milestone_type='finish' for finish milestones."""
+        from xer_mcp.parser.table_handlers.task import TaskHandler
+
+        handler = TaskHandler()
+
+        fields = [
+            "task_id",
+            "proj_id",
+            "task_code",
+            "task_name",
+            "task_type",
+            "milestone_type",
+        ]
+        values = [
+            "2002",
+            "1001",
+            "MS-END",
+            "Project Complete",
+            "TT_Mile",
+            "MS_Finish",
+        ]
+
+        result = handler.parse_row(fields, values)
+
+        assert result is not None
+        assert result["task_type"] == "TT_Mile"
+        assert result["milestone_type"] == "finish"
+
+    def test_parse_milestone_type_null_for_non_milestones(self) -> None:
+        """Handler should return None for milestone_type on non-milestone activities."""
+        from xer_mcp.parser.table_handlers.task import TaskHandler
+
+        handler = TaskHandler()
+
+        fields = [
+            "task_id",
+            "proj_id",
+            "task_code",
+            "task_name",
+            "task_type",
+        ]
+        values = [
+            "2003",
+            "1001",
+            "A1000",
+            "Regular Task",
+            "TT_Task",
+        ]
+
+        result = handler.parse_row(fields, values)
+
+        assert result is not None
+        assert result["task_type"] == "TT_Task"
+        assert result["milestone_type"] is None
+
+    def test_parse_milestone_type_derived_from_tt_mile(self) -> None:
+        """Handler should derive milestone_type='start' from task_type TT_Mile."""
+        from xer_mcp.parser.table_handlers.task import TaskHandler
+
+        handler = TaskHandler()
+
+        # No explicit milestone_type field - derive from task_type
+        fields = [
+            "task_id",
+            "proj_id",
+            "task_code",
+            "task_name",
+            "task_type",
+        ]
+        values = [
+            "2001",
+            "1001",
+            "MS-START",
+            "Project Start",
+            "TT_Mile",
+        ]
+
+        result = handler.parse_row(fields, values)
+
+        assert result is not None
+        assert result["task_type"] == "TT_Mile"
+        assert result["milestone_type"] == "start"
+
+    def test_parse_milestone_type_derived_from_tt_finmile(self) -> None:
+        """Handler should derive milestone_type='finish' from task_type TT_FinMile."""
+        from xer_mcp.parser.table_handlers.task import TaskHandler
+
+        handler = TaskHandler()
+
+        # TT_FinMile is a finish milestone
+        fields = [
+            "task_id",
+            "proj_id",
+            "task_code",
+            "task_name",
+            "task_type",
+        ]
+        values = [
+            "2002",
+            "1001",
+            "MS-END",
+            "Project Complete",
+            "TT_FinMile",
+        ]
+
+        result = handler.parse_row(fields, values)
+
+        assert result is not None
+        assert result["task_type"] == "TT_FinMile"
+        assert result["milestone_type"] == "finish"
+
 
 class TestTaskpredHandler:
     """Tests for TASKPRED table handler."""