Rename FABRIC series: FABRIC.md->0, FABRIC-2.md->1, FABRIC-3.md->2, FABRIC-4.md unchanged

FABRIC.md -> FABRIC-0.md
FABRIC-2.md -> FABRIC-1.md
FABRIC-3.md -> FABRIC-2.md (the current/living document)
FABRIC-4.md unchanged (new #3 to follow separately)

Every cross-reference repo-wide updated to match, including doc-comment
citations inside kernel source (.c/.h) files -- done via an ordered
placeholder substitution (FABRIC-3.md->placeholder2, FABRIC-2.md->
placeholder1, FABRIC.md->placeholder0, then placeholders resolved to
final names) in a single pass per file to avoid double-shifting
already-renamed references.

One line in capsules/font.4th grew past the 64-char block-format limit
as a side effect of the longer filename; shortened it and reverified
with mkcapsule --lint (34/34 pass) before rebuilding.

Verified 3-arch boot to ok> (amd64/aarch64/riscv64, each in the
foreground) after the fix; logs and DoE CSVs from this session's
verification runs included per this repo's own audit-artifact
convention.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019YcT3H2PQeyujrzjqS3Var

src/starkernel/hal/ttf.c

@@ -8,7 +8,7 @@
 */
 
 /**
- * ttf.c — TrueType font parser core (FABRIC.md items 4.3.7, 4.3.7a)
+ * ttf.c — TrueType font parser core (FABRIC-0.md items 4.3.7, 4.3.7a)
  *
  * sfnt directory + head/maxp/loca/glyf/cmap(format 4) table parsing, plus
  * simple- and composite-glyph outline extraction. All multi-byte fields in
@@ -26,7 +26,7 @@
  * an unsigned overflow check; q48_mul does a plain unsigned widen-multiply)
  * — confirmed by reading that file, not assumed. Per this repo's rule
  * against modifying a shared/tested module to "fix" it without being
- * asked, that gap is reported (see FABRIC.md's 4.3.7a completion note),
+ * asked, that gap is reported (see FABRIC-0.md's 4.3.7a completion note),
  * not patched here. No glyph in the v1 repertoire (§27.6.4) needs a
  * non-identity composite transform — checked against
  * fonts/JetBrainsMono-Regular.ttf before writing this, not assumed.