issues: mark 0041, 0042, 0043, 0047 FIXED

Triage pass: every issue file in `issues/` was re-verified against
HEAD. Three (0041, 0042, 0043) reproduce no longer — they were
silently fixed by adjacent work since the issue was filed. 0047
landed in the previous commit. All four header sections now lead
with **FIXED** + a one-line locator so the next reader doesn't
re-investigate.

After this, `issues/` is the actual open-issue list:

| Issue | Status |
|---|---|
| 0041 | FIXED (silently, by alias/parser work) |
| 0042 | FIXED (silently, type_alias_map lookup landed) |
| 0043 | FIXED (silently, lazy-lower foreign-class dispatch) |
| 0044 | FIXED |
| 0045 | FIXED |
| 0046 | FIXED |
| 0047 | FIXED (commit 0119c9c) |
| 0048 | FIXED (commit 0ede097) |
| 0049 | FIXED (commit b5301c4) |
| 0050 | FIXED (commit 5316bf7) |

No open issues remain. The files stay in tree as a record; new
issues take the next free number (0051).

issues/0047-run-output-on-stderr-runtime-on-stdout.md

@@ -1,3 +1,9 @@
+**FIXED** in commit `0119c9c`. Both `#run` output and the
+`--- build done ---` delimiter now write to fd 1 (stdout) via
+`std.c.write` from `core.flushInterpOutput` and main.zig's
+delimiter site. Test runner uses `2>&1` so snapshots are
+unaffected.
+
 # Symptom
 
 `#run print(...)` output lands on **stderr**; runtime `print(...)`