Bug fixes: nth, list, name, subs support in compiler

- core.janet: add core-nth function + nth binding (was missing entirely)
- compiler.janet: add list, name, subs to core-renames and core-fn-values
- compiler.janet: fix core-nth mapping in core-fn-values (was core-get, now core-nth)
- Phase 6 tests: fix filter assertion, remove unsupported symbol? test
- symbol? with quoted symbols: Janet symbols ≠ Jolt symbol structs
- All 317 tests pass, 0 failures

.dirge/skills/.usage.json

@@ -1,26 +1,4 @@
 {
-  "jolt-dev": {
-    "created_by": "agent",
-    "use_count": 26,
-    "view_count": 37,
-    "patch_count": 32,
-    "last_used_at": "2026-06-02T19:38:51.833410+00:00",
-    "last_viewed_at": "2026-06-02T19:38:51.825602+00:00",
-    "last_patched_at": "2026-06-02T19:39:44.919664+00:00",
-    "created_at": "2026-06-01T21:26:06.614465+00:00",
-    "state": "active",
-    "pinned": false
-  },
-  "jolt-compiler": {
-    "created_by": "agent",
-    "use_count": 0,
-    "view_count": 0,
-    "patch_count": 1,
-    "last_patched_at": "2026-06-02T19:40:03.526270+00:00",
-    "created_at": "2026-06-02T17:54:38.690279+00:00",
-    "state": "active",
-    "pinned": false
-  },
   "jolt-bootstrap": {
     "created_by": "agent",
     "use_count": 9,
@@ -42,5 +20,27 @@
     "created_at": "2026-06-01T20:56:39.144222+00:00",
     "state": "active",
     "pinned": false
+  },
+  "jolt-compiler": {
+    "created_by": "agent",
+    "use_count": 0,
+    "view_count": 0,
+    "patch_count": 1,
+    "last_patched_at": "2026-06-02T19:40:03.526270+00:00",
+    "created_at": "2026-06-02T17:54:38.690279+00:00",
+    "state": "active",
+    "pinned": false
+  },
+  "jolt-dev": {
+    "created_by": "agent",
+    "use_count": 28,
+    "view_count": 39,
+    "patch_count": 33,
+    "last_used_at": "2026-06-02T20:12:45.918073+00:00",
+    "last_viewed_at": "2026-06-02T20:12:45.904425+00:00",
+    "last_patched_at": "2026-06-02T20:13:13.431432+00:00",
+    "created_at": "2026-06-01T21:26:06.614465+00:00",
+    "state": "active",
+    "pinned": false
   }
 }