fix: progress always at 0% and context cancelled before sendDocument

- Fix progress template: remove spurious stderr: prefix and switch to
  _percent_str/_speed_str/_eta_str keys (progress.percent outputs NA
  for HLS streams with unknown total size)
- Update progress regex to match new template format:
  DLPROG| 45.2%|   1.05MiB/s|00:45
- Fix context cancellation bug: clearActiveJob was cancelling dlCtx
  before handleDownloadCompletion could send the document
- Update progress test cases to match new template output format

internal/dl/progress_test.go

@@ -109,21 +109,21 @@ func TestParseProgressTemplate(t *testing.T) {
 		hasRes bool
 	}{
 		{
-			line:   "DLPROG|45.2|2.34MiB/s|00:45",
+			line:   "DLPROG| 45.2%|   2.34MiB/s|00:45",
 			pct:    45.2,
 			speed:  "2.34MiB/s",
 			eta:    "00:45",
 			hasRes: true,
 		},
 		{
-			line:   "DLPROG|100.0|5.00MiB/s|00:00",
+			line:   "DLPROG|100.0%|   5.00MiB/s|00:00",
 			pct:    100.0,
 			speed:  "5.00MiB/s",
 			eta:    "00:00",
 			hasRes: true,
 		},
 		{
-			line:   "DLPROG|0.0||",
+			line:   "DLPROG|  0.0%||",
 			pct:    0.0,
 			speed:  "",
 			eta:    "",
@@ -142,12 +142,26 @@ func TestParseProgressTemplate(t *testing.T) {
 			hasRes: false,
 		},
 		{
-			line:   "DLPROG|50.0|Unknown|Unknown",
+			line:   "DLPROG| 50.0%|     Unknown|Unknown",
 			pct:    50.0,
 			speed:  "",
 			eta:    "",
 			hasRes: true,
 		},
+		{
+			line:   "DLPROG| 16.7%|   1.05KiB/s|Unknown",
+			pct:    16.7,
+			speed:  "1.05KiB/s",
+			eta:    "",
+			hasRes: true,
+		},
+		{
+			line:   "DLPROG| 11.1%| 754.59KiB/s|00:08",
+			pct:    11.1,
+			speed:  "754.59KiB/s",
+			eta:    "00:08",
+			hasRes: true,
+		},
 	}
 	for _, tt := range tests {
 		got := parseProgressTemplate(tt.line)