feat(v4.0.0): reading a line and splitting it into words and numbers

The first layer of the compiler capsule, on the host node: TIB >IN SPAN
SOURCE BL EXPECT QUERY WORD ENCLOSE CONVERT NUMBER and the comment
words.  The definitions are text, v4/capsule/core.v4 (the core words
they rest on) and v4/capsule/input.v4, assembled by the text assembler,
which can now read a file.

EXPECT, QUERY, WORD and ENCLOSE behave as v3's.  CONVERT and NUMBER are
FORTH-79 (ruled 2026-10-04): any BASE, a double in the standard order,
and NUMBER returns a signed double or sets NODE-ERROR.

Executed at both cell widths against C and against values recorded from
the v3 binary.

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

docs/v4.0.0/DECOMPOSITION.md

@@ -566,11 +566,11 @@ width and print a flood of spaces.
 | `SEARCH` | CAP | `( a1 u1 a2 u2 -- a3 u3 flag )`: the rest of string 1 from the first place string 2 occurs and `-1`, or string 1 and `0`; an empty string 2 is found at the start. See below; the inner comparison is in line, not a call to `COMPARE`. Same notes. Executed on the golden model (2026-10-03), including a transcript of the v3 binary. Leaves its caller 3 data cells and 5 return entries. Clobbers `A` and `B`. |
 | `SCAN` `SKIP` | CAP | `( baddr u c -- baddr' u' )`: `SCAN` stops at the first byte equal to the low byte of `c` (or at the end, with `u' = 0`); `SKIP` stops at the first byte not equal to it. See below. A negative count reads as 0, as v3. v3's counted-string auto-detection is not kept. Executed on the golden model (2026-10-03), including a transcript of the v3 binary. Each leaves its caller 5 data cells and 5 return entries. Clobber `A`. |
 | `(S)` | CAP | Variable, 4 cells: `COMPARE`'s two lengths; `SEARCH`'s string 2 and the whole of string 1. |
-| `BL` | IN | `32` |
-| `EXPECT` `QUERY` | CC | Built on `KEY` (DEV). |
-| `SPAN` `TIB` `>IN` `SOURCE` | CC | Interpreter state on the host node. |
-| `WORD` `ENCLOSE` | CC | Parser. |
-| `NUMBER` `CONVERT` | CC | Rewritten to honour `BASE` (v3's `NUMBER` is base 10 only). |
+| `BL` | IN | `32` — executed on the golden model (2026-10-04). |
+| `EXPECT` `QUERY` | CC | Built on `KEY` (DEV); source in `v4/capsule/input.v4`. `EXPECT ( baddr u -- )` as v3's `fgets`: at most `u-1` characters, stopping after a new-line (taken, not stored), then a zero; `SPAN` is the count; a line that does not fit leaves its tail to be read next; `u < 0` does nothing and sets `NODE-ERROR`. `QUERY` is `TIB #TIB EXPECT  0 >IN !` with `#TIB` 1025, as v3. Executed on the golden model's host node (2026-10-04), including results recorded from the v3 binary. Both part from FORTH-79, which takes up to `u` characters in `EXPECT` and 80 in `QUERY`: reported 2026-10-04, awaiting a ruling. `EXPECT` leaves its caller 6 data cells and 4 return entries. |
+| `SPAN` `TIB` `>IN` `SOURCE` | CC | Interpreter state on the host node. `TIB` is the buffer's byte address and `>IN` and `SPAN` their variables' word addresses, all in line; `SOURCE ( -- baddr u )` is `TIB` and `SPAN @`, a negative `SPAN` read as 0. Executed on the golden model's host node (2026-10-04). |
+| `WORD` `ENCLOSE` | CC | Parser; source in `v4/capsule/input.v4`. `WORD ( c -- baddr )`, as v3: the next word of `TIB` delimited by `c`, as a counted string in a 64-byte buffer with a zero after it; delimiters before it are skipped and so are all those after it; a longer word is cut to 62 characters; at the end of the line the count is 0. `ENCLOSE ( baddr c -- baddr n1 n2 n3 )` on a zero-terminated string. Executed on the golden model's host node (2026-10-04) against C and the counts and `>IN` values recorded from the v3 binary (the text in v3's own buffer was corrupt in those runs: `hello` came back as `hlllo`). `WORD` parts from FORTH-79 in skipping every trailing delimiter, storing a zero where the standard stores the delimiter, and cutting at 62: reported 2026-10-04, awaiting a ruling. `WORD` leaves its caller 4 data cells and 3 return entries. |
+| `NUMBER` `CONVERT` | CC | FORTH-79, not v3 (ruled 2026-10-04); source in `v4/capsule/input.v4`. `CONVERT ( d1 baddr1 -- d2 baddr2 )` takes the characters from `baddr1 + 1` on as digits in the current `BASE`, in either case, accumulating each into the double after multiplying it by `BASE`, and stops at the first that is not one; the double is `( lo hi )`. v3's was base 10 only, started at `baddr1`, and took the double low cell on top. `NUMBER ( baddr -- d )` is the counted string as a signed double in the current `BASE`, with an optional leading minus; anything else gives 0 and sets `NODE-ERROR`. v3's returned `( n flag )` in base 10. Executed on the golden model's host node (2026-10-04) against C in eight bases, including a digit that carries out of the low cell. `NUMBER` leaves its caller 3 data cells and 3 return entries. |
 | `S"` `(s")` `[']` | CC | Compiler words. |
 | `LITERAL` `[LITERAL]` (placeholders) | RET | The working `LITERAL` is in §5.17. |
 
@@ -690,7 +690,7 @@ The storage service belongs to the Artemis role, now a device node.
 
 | Word | Fate | Notes |
 | --- | --- | --- |
-| `(` `\` | CC |  |
+| `(` `\` | CC | `(` is `41 WORD drop`; `\` is `SPAN @ >IN !`. In `v4/capsule/input.v4` under the names `PAREN` and `BACKSLASH`. Executed on the golden model's host node (2026-10-04). |
 | `EXECUTE` | CAP | `push ;` (tail-jumps to the xt; the xt returns to `EXECUTE`'s caller) |
 | `NOP` | OP | `nop` |
 | `QUIT` `ABORT` `ABORT"` `(ABORT")` `COLD` `WARM` | CC |  |