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/console.c

@@ -164,7 +164,7 @@ static int serial_transmit_empty(void) {
  *
  * g_active_vm_name_buf owns the storage -- console_set_vm_name() copies
  * into it rather than storing the caller's own pointer. Found live
- * 2026-08-28 (FABRIC-3.md Phase F): mama_word_use() (USE) passes
+ * 2026-08-28 (FABRIC-2.md Phase F): mama_word_use() (USE) passes
  * entry.name, a local VMRegistryEntry's own field -- once USE returns,
  * that stack frame is reused and the old raw-pointer version left
  * g_active_vm_name dangling, corrupting every console tag after the
@@ -229,7 +229,7 @@ static void raw_putc(char c) {
  * framebuffer (vt100_putc) -- mirrors console_putc()'s own serial/framebuffer
  * split so the prefix reaches both outputs, not serial only. No recursion
  * into console_putc itself (would re-trigger the line-start prefix check). */
-/* FABRIC.md 4.4: the bracketed VM name (brackets included) renders in
+/* FABRIC-0.md 4.4: the bracketed VM name (brackets included) renders in
  * standard web orange, 0xFFA500 -- not in the classic 16-color ANSI
  * palette, so sent as a literal 24-bit SGR sequence rather than a palette
  * index. Same dual serial+framebuffer send pattern as the rest of this