refactor(v4.0.0): the capsule's inner words keep their state in memory

WORD, the dictionary words and the code generator run underneath
whatever the user has on the stacks, which are ten and nine deep (D-2).
Measured, they used five to seven data cells of their own, leaving a
line about three.  Each now keeps what it works on in its file's
scratch cells and has at most three cells on the data stack; , calls
nothing; and the longest chains of calls are shorter.

The public words of core.v4, input.v4 and dict.v4 get dictionary
headers.  NUMBER is split so the interpreter can have a flag instead of
NODE-ERROR.  The host-node tests share one memory map, host_map.h.

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

docs/v4.0.0/DECOMPOSITION.md

@@ -572,8 +572,8 @@ width and print a flood of spaces.
 | `BL` | IN | `32` — executed on the golden model (2026-10-04). |
 | `EXPECT` `QUERY` | CC | Built on `KEY` (DEV); source in `v4/capsule/input.v4`. FORTH-79 (ruled 2026-10-04). `EXPECT ( baddr n -- )` stores characters from `baddr` upward until a new-line (taken, not stored) or until `n` have been received, then a zero; no action for `n <= 0`; a line longer than `n` leaves the rest to be read next. It also sets `SPAN`, which is not FORTH-79 but is v3's. `QUERY` is `TIB 80 EXPECT  0 >IN !`. v3's `EXPECT` was C's `fgets` and took `n-1` characters, and its `QUERY` took 1024. Executed on the golden model's host node (2026-10-04) against C for every size and line length. `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 )` is FORTH-79 (ruled 2026-10-04): characters are taken from `TIB` until the delimiter `c` or the end of the text, leading delimiters ignored, and stored as a counted string; the delimiter met (`c`, or a zero if the text ran out) is stored after them, uncounted; `>IN` is left just past it; with nothing left the count is 0. The count is a byte, so a word over 255 characters is cut to 255; the buffer is 257 bytes. v3's `WORD` skipped every delimiter after the word, always stored a zero, and cut at 62. `ENCLOSE ( baddr c -- baddr n1 n2 n3 )`, not a FORTH-79 word, works on a zero-terminated string as v3's. Executed on the golden model's host node (2026-10-04) against C, and `ENCLOSE` against values recorded from the v3 binary. `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. |
+| `WORD` `ENCLOSE` | CC | Parser; source in `v4/capsule/input.v4`. `WORD ( c -- baddr )` is FORTH-79 (ruled 2026-10-04): characters are taken from `TIB` until the delimiter `c` or the end of the text, leading delimiters ignored, and stored as a counted string; the delimiter met (`c`, or a zero if the text ran out) is stored after them, uncounted; `>IN` is left just past it; with nothing left the count is 0. The count is a byte, so a word over 255 characters is cut to 255; the buffer is 257 bytes. v3's `WORD` skipped every delimiter after the word, always stored a zero, and cut at 62. `ENCLOSE ( baddr c -- baddr n1 n2 n3 )`, not a FORTH-79 word, works on a zero-terminated string as v3's. Executed on the golden model's host node (2026-10-04) against C, and `ENCLOSE` against values recorded from the v3 binary. `WORD` keeps what it works on in memory and has at most three cells of its own on the data stack: it leaves its caller 7 data cells and 6 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 2 return entries; the interpreter does not use it (it has a single-cell conversion of its own that needs far less of the stack). |
 | `S"` `(s")` `[']` | CC | Compiler words. |
 | `LITERAL` `[LITERAL]` (placeholders) | RET | The working `LITERAL` is in §5.17. |
 
@@ -674,14 +674,14 @@ The storage service belongs to the Artemis role, now a device node.
 
 | Word | Fate | Notes |
 | --- | --- | --- |
-| `HERE` `ALIGN` `ALLOT` `,` `C,` `2,` `PAD` `LATEST` | CC | The dictionary lives on the host node; source in `v4/capsule/dict.v4`. The dictionary pointer `DP` is a byte address, so `C,` packs four characters to a cell; `HERE` is the next whole cell (a word address); `,` and `ALLOT` align first. An address unit is a cell (D-1), so `ALLOT` counts cells where v3's counted bytes; a negative count gives space back. `2,` stores the low cell first, as v3. Going outside the dictionary space stores nothing, moves nothing and sets `NODE-ERROR`. `PAD` is a fixed scratch area, as in v3, given as a byte address. `LATEST` is the xt of the newest entry, 0 if there is none (v3's pushes `HERE`, which looks like a bug; reported, not changed). Executed on the golden model's host node (2026-10-04). `,` and `ALLOT` leave their caller 6 data cells and 5 return entries. |
+| `HERE` `ALIGN` `ALLOT` `,` `C,` `2,` `PAD` `LATEST` | CC | The dictionary lives on the host node; source in `v4/capsule/dict.v4`. The dictionary pointer `DP` is a byte address, so `C,` packs four characters to a cell; `HERE` is the next whole cell (a word address); `,` and `ALLOT` align first. An address unit is a cell (D-1), so `ALLOT` counts cells where v3's counted bytes; a negative count gives space back. `2,` stores the low cell first, as v3. Going outside the dictionary space stores nothing, moves nothing and sets `NODE-ERROR`. `PAD` is a fixed scratch area, as in v3, given as a byte address. `LATEST` is the xt of the newest entry, 0 if there is none (v3's pushes `HERE`, which looks like a bug; reported, not changed). Executed on the golden model's host node (2026-10-04). `,` calls nothing and leaves its caller 7 data cells and 8 return entries; `ALLOT` leaves 7 and 7. |
 | `SP@` `SP!` | RET | No visible stack pointer (D-2). |
 
 ### 5.13 Dictionary manipulation
 
 | Word | Fate |
 | --- | --- |
-| `FIND` | CC | `( -- xt \| 0 )`, FORTH-79 and v3 alike: the compilation address of the next word in the input stream, or 0 if it is not in the dictionary. `32 WORD` then a search from the newest entry back, skipping hidden ones; names are case sensitive, as v3, and 31 characters are significant (FORTH-79). Executed on the golden model's host node (2026-10-04) against a list kept in C, 300 entries. Leaves its caller 4 data cells and 2 return entries. |
+| `FIND` | CC | `( -- xt \| 0 )`, FORTH-79 and v3 alike: the compilation address of the next word in the input stream, or 0 if it is not in the dictionary. `32 WORD` then a search from the newest entry back, skipping hidden ones; names are case sensitive, as v3, and 31 characters are significant (FORTH-79). Executed on the golden model's host node (2026-10-04) against a list kept in C, 300 entries. Leaves its caller 7 data cells and 5 return entries. |
 | `'` | CC | `( -- addr )`, FORTH-79: the parameter field address of the next word in the input stream; not found is an error (0, and `NODE-ERROR` set). v3's `'` returned what `FIND` returns. For a word that is code the two are the same address; for a data word the parameter field is the cell after its code, which is what FORTH-79's `n ' NAME !` needs. Its compiling behaviour comes with the compiler words. Executed on the golden model's host node (2026-10-04). |
 | `>LINK` `LFA` `LINK>` `>NAME` `NFA` `NAME>` `CFA` `PFA` `>BODY` `TRAVERSE` | CC | The fields of an entry, all reached from its xt, as in v3 where the xt was the entry: `>LINK`/`LFA` the link's address, `LINK>` the older entry's xt, `>NAME`/`NFA` the byte address of the counted name, `NAME>` back to the xt, `CFA` the xt itself, `PFA`/`>BODY` the parameter field, `TRAVERSE` from a name's count byte to past its last character (for `n > 0`; otherwise unchanged, as v3). Executed on the golden model's host node (2026-10-04). |
 | `SMUDGE` `HIDDEN` | CC | `SMUDGE` toggles the hidden flag of the newest entry; `HIDDEN` sets it. v3 refuses both outside compilation; that check comes with the compiler words. Executed on the golden model's host node (2026-10-04). |