feature: boot.mgr replace hardcoded init sequence with dependency-driven boot manager

Introduce boot.mgr - a self-registering, dependency-ordered boot
initialization framework with barrier-based phasing and glob pattern
matching. Units now declare their own init procedures and dependencies
via registerBoot()/registerBarrier() in their initialization sections,
boot.mgr.run() topologically sorts and executes them.

- Add src/boot/boot.mgr.pas with topoSort, glob matching, barrier
  two-pass algorithm, and boot tree printer
- Gut src/asuro.pas (kmain): now just stores multiboot info, calls
  System.init(), boot.mgr.run, and yield()
- Add initialization sections with registerBoot() to 53 existing units
- Add new units: core.pas, test.pas, driver.storage.boot.pas,
  app.wasm.pas, app.bsod.pas (factored out of asuro.pas)
- Define 9 barrier phases: immediate -> early -> middle -> storage ->
  bus -> device -> bus.late -> late -> final
- Fix xHCI ISR: exclude PRC/WRC from PORTSC change bit clearing to
  prevent race with port reset busy-wait
- Fix driver.bus.usb.core fire_completion_hooks: guard against uint32
  underflow when CompletionHookCount = 0
- Move auto_mount_volumes from device barrier to late barrier so it
  runs after PCI scan discovers storage controllers
- Add toolchain/compile_initcalls.sh for boot entry extraction
- Add Boot Registration sections to all 51 doc files; create 4 new
  doc files; rewrite boot.mgr.md; update mkdocs.yml nav

toolchain/compile.sh

@@ -29,6 +29,7 @@ declare -a run_steps=(
 	"compile_icons.sh" "Failed to generate icons!"
 	"compile_wasuro.sh" "Failed to pull Wasuro!"
 	"compile_sources.sh" "Failed to compile FPC Sources!"
+	"compile_initcalls.sh" "Failed to generate INITFINAL table!"
 	"compile_link.sh" "Failed linking!"
 	"compile_isogen.sh" "Failed to create ISO!"
 	"compile_docs.sh" "Failed to generate documentation!"

toolchain/compile_initcalls.sh

@@ -0,0 +1,104 @@
+#!/usr/bin/env bash
+echo " "
+echo "======================="
+echo " "
+echo "Generating INITFINAL table..."
+echo " "
+
+# ---------------------------------------------------------------------------
+# compile_initcalls.sh
+#
+# Scans every compiled FPC object file (lib/*.o) for INIT$_$* symbols.
+# FPC emits these for every unit that has an 'initialization' section.
+# We generate a small C source file that builds an INITFINAL table
+# (matching the TInitFinalTable layout in system.pas) and compile it
+# to lib/initcalls.o.  FPC_INITIALIZEUNITS in system.pas walks this
+# table at boot to call each unit's initialization code.
+# ---------------------------------------------------------------------------
+
+INIT_SYMBOLS=()
+
+for obj in lib/*.o; do
+    # Skip non-FPC objects that will never contain Pascal init sections
+    case "$(basename "$obj")" in
+        stub.o|splash_tga.o|initcalls.o) continue ;;
+    esac
+
+    # nm --defined-only: only symbols defined in this object (not extern refs)
+    # grep ' T INIT\$_\$': global text symbols matching FPC's naming convention
+    # awk '{print $3}': extract the symbol name (third field)
+    while IFS= read -r sym; do
+        [ -n "$sym" ] && INIT_SYMBOLS+=("$sym")
+    done < <(nm --defined-only "$obj" 2>/dev/null | grep ' T INIT\$_\$' | awk '{print $3}')
+done
+
+COUNT=${#INIT_SYMBOLS[@]}
+echo "Found $COUNT unit initialization section(s)."
+
+CFILE="/tmp/initcalls.c"
+
+# ---- Generate the C source file ----
+
+cat > "$CFILE" <<'HEADER'
+/* initcalls.c — Auto-generated INITFINAL dispatch table.
+ * DO NOT EDIT — regenerated on every build by compile_initcalls.sh.
+ *
+ * Provides the INITFINAL symbol expected by FPC_INITIALIZEUNITS in
+ * system.pas.  Each unit with a Pascal 'initialization' section gets
+ * an entry so its init code runs during system.init(). */
+
+typedef void (*initproc_t)(void);
+
+typedef struct {
+    initproc_t init;
+    initproc_t fini;
+} __attribute__((packed)) TInitFinalRec;
+
+HEADER
+
+# Emit extern declarations — use asm("INIT$_$UNIT.NAME") labels so
+# GCC references the exact FPC-generated symbol names (which contain
+# $ and . characters that are valid in ELF but not in C identifiers).
+IDX=0
+for sym in "${INIT_SYMBOLS[@]}"; do
+    echo "  -> $sym"
+    printf 'extern void initcall_%d(void) asm("%s");\n' "$IDX" "$sym" >> "$CFILE"
+    IDX=$((IDX + 1))
+done
+
+# Emit the INITFINAL table struct
+if [ "$COUNT" -eq 0 ]; then
+    cat >> "$CFILE" <<'ZEROTABLE'
+
+/* No initialization sections found — emit an empty table */
+struct __attribute__((packed)) {
+    int count;
+} INITFINAL = { 0 };
+ZEROTABLE
+else
+    printf '\nstruct __attribute__((packed)) {\n' >> "$CFILE"
+    printf '    int count;\n' >> "$CFILE"
+    printf '    TInitFinalRec procs[%d];\n' "$COUNT" >> "$CFILE"
+    printf '} INITFINAL = {\n' >> "$CFILE"
+    printf '    %d,\n' "$COUNT" >> "$CFILE"
+    printf '    {\n' >> "$CFILE"
+
+    for ((i=0; i<COUNT; i++)); do
+        COMMA=","
+        [ "$i" -eq $((COUNT - 1)) ] && COMMA=""
+        printf '        { initcall_%d, (initproc_t)0 }%s\n' "$i" "$COMMA" >> "$CFILE"
+    done
+
+    printf '    }\n' >> "$CFILE"
+    printf '};\n' >> "$CFILE"
+fi
+
+echo " "
+echo "--- Generated C source ---"
+cat "$CFILE"
+echo "--- End of generated C source ---"
+echo " "
+
+# Compile to a 32-bit ELF object file
+gcc -m32 -c -fno-pic -ffreestanding -o lib/initcalls.o "$CFILE"
+echo "Compiled lib/initcalls.o"