feat(types): Dict + Set string-keyed containers (#54)

Types phase 4 — containers. A splice-on-demand open-addressing hash table
(runtime/native/dict.ludic, FNV-1a, linear probing, tombstones, grow at 0.7)
behind two namespaces:

- Dict.* — string -> int map: new/set/get/get_or/has/remove/size/clear/keys.
  Resource counts, id/name registries. O(1) average vs a linear list scan.
- Set.* — set of strings: new/add/has/remove/size/clear/members. Tags,
  unlocked achievements, visited tiles. Shares the same table.

Values are int (also an entity handle / small id); Value.* covers richer
maps. [T; N] inline fixed arrays remain future work — typed buffers and []T
slices already cover heap-backed arrays.

Wired: parser splice trigger (g_uses_dict), emit_call dispatch, reseeded seed,
a self-asserting example (examples/library/containers.ludic + feat_case), and
per-symbol docs + inventory. All suites green incl. golden renders byte-
identical and the bootstrap fixpoint.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

changes/types-containers.md

@@ -0,0 +1,13 @@
+bump: minor
+type: feat
+**Containers — `Dict` + `Set` (#54, types phase 4).** Everyday string-keyed
+lookups backed by one open-addressing hash table (FNV-1a, linear probing,
+tombstone deletes, grows at load factor 0.7), spliced in on demand.
+`Dict.*` maps string keys to `int` values — `new`/`set`/`get`/`get_or`/`has`/
+`remove`/`size`/`clear`/`keys` — for resource counts and id/name registries.
+`Set.*` is a set of string members — `new`/`add`/`has`/`remove`/`size`/`clear`/
+`members` — for tags, unlocked achievements and visited tiles. O(1) average
+lookup instead of a linear list scan. Values are `int` (also holds an `entity`
+or any small id); the `Value.*` tree already covers richer/heterogeneous maps,
+and `[T; N]` inline fixed arrays remain future work (typed buffers `words` /
+`fixeds` / `pointers` and `[]T` slices cover heap-backed arrays today).