play 2's frame keeps and a dropped file: a var() join made at once, the hint rail emptied in place, save_read gives its text back

- ludic.ui cv_join (units_pieces.ludic:93): a var() value's pieces were joined by +, a text left
  behind per piece on every memo miss; it is written at its length at once (units_join.ludic), and
  the miss is its own declared function (cs_vars_miss), bounded by the memo.
- ludic.hints hn_slots (rail.ludic:41): hints_reset made a new rail every time; the rail is
  emptied in place, made again only for another count (rail_slots.ludic).
- value_spare_put (value.ludic:138): a list's spares grow only past the most it has ever cut off;
  declared as such.
- ludic.save: save_read reads, parses and frees the file's text - the tree's strings are the
  parser's own - and says whether the text was whole (SaveRead.intact) for the words of a refusal.
  Maroon Lake's trip and home reads kept the whole file on every load and every menu card read.

Tests: ludic.save (10), ludic.hints (8); the 36 ui examples; value_list_regrow, json_saves and
alloc_fence_declared unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.save/read.ludic

@@ -13,7 +13,17 @@ export function save_parse(text: string, f: SaveFormat) -> SaveRead {
   return read_new(SAVE_OK, v)
 }
 
-export function save_read(path: string, f: SaveFormat) -> SaveRead { return save_parse(Fs.read_text(path), f) }
+# the file read and parsed, and its text given back - the tree's strings are the parser's own, and a
+# load that kept the whole file for good kept it on every load and every menu card read
+export function save_read(path: string, f: SaveFormat) -> SaveRead {
+  let text = Fs.read_text(path)
+  let r = save_parse(text, f)
+  if text != null {
+    r.intact = save_text_intact(text)
+    free(text)
+  }
+  return r
+}
 
 # The version checks, then the chain. True when the object is now in today's shape; a newer file is
 # SAVE_FUTURE and read-only, an older one than the format carries is SAVE_CORRUPT.