fix(v4): the final review's six minors in the ROM boot

- Text after start is refused, as text.c refuses it: before it jumps, the
  ROM reads on to the end of the source; blanks, comments and the ends of
  blobs may follow, a token is ERR-AFTER (26), "text after start".
- A token too long where a name, a target or a value is wanted is "name
  too long", as text.c says: (MISSING) reports "missing" only when no error
  came first.  `", keeps "missing", which is text.c's word for both.
- text.c's "address out of range" names the address, not the value.
- The system's source files are one list, v4/sys_files.h: boot.c, the
  harness and the nucleus test are made from it.
- The ROM's error codes and words are one list, v4/rom_errors.h: boot.c's
  messages, host_map.h's ROM_ERR_* and mkmap's ERR-* are made from it.
- node.h says what v4_node_store does with a ROM address (nothing, as for
  any address outside RAM, D-14); test_host_rom_range pins it.

ROM: 2095 words, rom_hash 0x06d0dcb7a0cb41a1.  dict_hash unchanged,
0xe5a57f3eb72ff94a.  make -C v4 test test-32 hosted-check pass.  QEMU:
amd64, aarch64, riscv64 to ok>, POST 538/538, POST: PASSED.

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

v4/tests/host_map.h

@@ -12,6 +12,7 @@
 #ifndef V4_TESTS_HOST_MAP_H
 #define V4_TESTS_HOST_MAP_H
 
+#include "v4/rom_errors.h"
 #include "v4/blocks.h"
 #include "v4/text.h"
 #include <stdio.h>
@@ -197,32 +198,9 @@
 #define ROM_KIND_CONST 2
 #define ROM_KIND_MACRO 3
 #define ROM_KIND_SET   4
-/* the ROM's error codes */
-#define ROM_ERR_TOO_LONG  1                     /* a token longer than 63 characters: "name too long" */
-#define ROM_ERR_COMMENT   2                     /* a ( with no ) before the end: "comment not closed" */
-#define ROM_ERR_BAD_NAME  3                     /* an opcode, a reserved word, a label, a number or &...: "cannot be used as a name" */
-#define ROM_ERR_DEFINED   4                     /* "already defined" */
-#define ROM_ERR_NAMES     5                     /* the symbol table is full: "too many names" */
-#define ROM_ERR_FIT       6                     /* memory is full, or a branch cannot reach: "does not fit" */
-#define ROM_ERR_OPCODE    7                     /* not an opcode the packer takes there */
-#define ROM_ERR_IN_MACRO  8                     /* "not allowed in a macro" */
-#define ROM_ERR_MACRO     9                     /* "macro without endmacro", "endmacro without macro" */
-#define ROM_ERR_LABEL_DUP 10                    /* "label already defined in this word" */
-#define ROM_ERR_LABELS    11                    /* "too many labels in one word" */
-#define ROM_ERR_FOR       12                    /* FOR nested too deep, NEXT or UNEXT without FOR, FOR without NEXT */
-#define ROM_ERR_UNEXT     13                    /* "FOR ... UNEXT must fit one instruction word and hold no literal" */
-#define ROM_ERR_TARGET    14                    /* "not something to branch to" */
-#define ROM_ERR_UNDEFINED 15                    /* "never defined" */
-#define ROM_ERR_BIG       16                    /* "number does not fit a cell" */
-#define ROM_ERR_AMP       17                    /* "& needs a word that is already defined" */
-#define ROM_ERR_FETCH_P   18                    /* "write the number, not @p" */
-#define ROM_ERR_MISSING   19                    /* a name, a target, a value or a string missing at the end */
-#define ROM_ERR_DEEP      20                    /* "macros nested too deep" */
-#define ROM_ERR_REFS      21                    /* "too many unresolved branches" */
-#define ROM_ERR_VALUE     22                    /* "not a value", "not a number" */
-#define ROM_ERR_NO_START  23                    /* the input ended with no start */
-#define ROM_ERR_START     24                    /* start: not a word */
-#define ROM_ERR_RANGE     25                    /* "address out of range": store outside RAM */
+/* the ROM's error codes: ROM_ERR_TOO_LONG, ROM_ERR_COMMENT ... (v4/rom_errors.h) */
+#define ROM_ERR_ENUM_(name, code, text) ROM_ERR_##name = code,
+enum { V4_ROM_ERRORS(ROM_ERR_ENUM_) ROM_ERR_END_ };
 #define ROM_ADDR_TOP      ((v4_cell)(V4_NODE_WORDS + V4_ROM_WORDS - 1u))   /* the top of the address space */
 #define WORD_DEFINED   (BUF0_W - 11)             /* the xt of the word that is told of each new entry, or 0 */
 #define WORD_FORGOTTEN (BUF0_W - 12)             /* the xt of the word that is told when entries go, or 0 */