Typed arguments, calculated tables, spans, closed-world fonts, top-level fnt/ and env/

Sync with klammertext-dev through b90b0e09:

- Argument types end to end: :python_cast values are applied (Python
  @eval receives real bools/numbers/lists), argument values are
  validated against their argtype patterns with the argtype's
  description as the error message, argtypes can declare :default
  (overridable per declaration), and parameterized type families are
  supported: rest(N) casts a rest argument to an N-dimensional list
  (bar-count = dimension).
- Unified indexed_range syntax (selector with parenthesized subsets,
  composable mnemonic names) for table lines and spans.
- Table klammer: caption fonts fixed in both targets, :column_width /
  :leading / :colsep wired, :colspan and :rowspan render (HTML
  attributes; \multicolumn / \multirow), calculated cell values (:calc)
  with prefix operators, display-precision semantics, :calc_format and
  :decimal period|comma.
- Fonts: closed-world resolution on the Klammertext font store
  (infrastructure in mac/font_store; no Google Fonts links or fetch).
  Default fonts live in the top-level fnt/; additional fonts install
  into KLAMMERTEXT_FONTS directories via kdesc --font (list, samples,
  preview, install — classification by font metadata).  CSS font family
  names are quoted (digit-initial families were silently lost).
- Environment files moved from mac/env/ to the top-level env/; shell
  profiles source env/runtime.env.  Dead per-host variants removed.
- Container: fnt/ ships in the image; curl removed (no network use).

sks/kutil/kutil.k

@@ -1,9 +1,15 @@
 @@show s : @eval :cpp show show @ @@
 
+@@@argtype caption_side |
+  the side of its element on which a caption is placed
+  :pattern top^|right^|bottom^|left
+  :default bottom
+@@@
+
 @@caption_arguments :
   :caption
   :number.bool true
-  :caption_side.side bottom
+  :caption_side.caption_side
   :caption_font.font i
   :caption_font_size.float .9
 @@
@@ -29,14 +35,6 @@
   #:python_cast (lambda s : [__import__("kutil").parse_length("tex", e) for e in s.split()])
 @@@
 
-@@@argtype side | a side of a box
-  :pattern top^|right^|bottom^|left
-@@@
-
-@@@argtype hpos | horizontal position
-  :pattern left^|center^|right^|none
-@@@
-
 @@@argtype figure_id |
 an identifier for a figure.