Baseline: Ludic compiler + toolchain, Phase 1 syntax fixes complete

Self-hosted compiler (selfhost/*.ludic), runtime, examples, editor tooling,
and docs. Phase 1 of the syntax-redesign cohesion pass has landed:
edge-system fix, signature-query, when-alias, and the documentation truth-pass.
Suite green (14/14), C-free bootstrap fixpoint holds.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

selfhost/tests/control.ludic

@@ -0,0 +1,13 @@
+game T {
+  fn fib(n: int) -> int { if n < 2 { return n }  return fib(n-1) + fib(n-2) }
+  main {
+    print_int(fib(10))                 # 55
+    let s = 0
+    for i in 0 .. 10 { if i == 5 { break }  if i % 2 == 0 { continue }  s = s + i }
+    print_int(s)                       # 1+3 = 4
+    let i = 0  let t = 0
+    while true { i = i + 1  if i > 5 { break }  t = t + i }
+    print_int(t)                       # 15
+    if false and (1/0 == 0) { print_int(999) } else { print_int(1) }   # short-circuit: no div by zero
+  }
+}

selfhost/tests/fixed.ludic

@@ -0,0 +1,12 @@
+game T {
+  main {
+    let half = 0.5
+    let a = 1.5
+    print_int(flr(a + half))          # flr(2.0) = 2
+    print_int(flr(a * 2.0))           # flr(3.0) = 3
+    let third = 1.0 / 3.0
+    print_int(flr(third * 3.0))       # ~flr(1.0) = 1 (may be 0 with rounding)
+    print_int(flr(fx(5) + a))         # flr(6.5) = 6
+    if a > half { print_int(1) } else { print_int(0) }   # 1
+  }
+}

selfhost/tests/match_bits.ludic

@@ -0,0 +1,16 @@
+game T {
+  fn classify(c: int) -> int {
+    match c { 65, 66 => { return 1 }  67 => { return 2 }  _ => { return 9 } }
+    return 0
+  }
+  main {
+    print_int(classify(65))          # 1
+    print_int(classify(67))          # 2
+    print_int(classify(90))          # 9
+    print_int(shl(1, 4))             # 16
+    print_int(band(bor(4, 1), 6))    # 4
+    let p = mem_alloc(16)
+    poke32(p, 1, 9999)
+    print_int(peek32(p, 1))          # 9999
+  }
+}

selfhost/tests/slices.ludic

@@ -0,0 +1,11 @@
+game T {
+  main {
+    let xs = new []int
+    print_int(len(xs))       # 0
+    for i in 0 .. 20 { push(xs, i * i) }
+    print_int(len(xs))       # 20
+    print_int(xs[19])        # 361
+    xs[3] = 777
+    print_int(xs[3])         # 777
+  }
+}

selfhost/tests/structs.ludic

@@ -0,0 +1,20 @@
+game T {
+  struct P { x: int = 0, y: int = 7, next: P }
+  fn bump(p: P) -> void { p.x = p.x + 100 }
+  main {
+    let a = new P
+    print_int(a.y)            # 7 default
+    a.x = 5
+    let b = a
+    b.x = 9
+    print_int(a.x)            # 9 (reference)
+    bump(a)
+    print_int(a.x)            # 109
+    let c = new P
+    c.x = 2
+    a.next = c
+    print_int(a.next.x)      # 2 chained
+    a.next.x = 42
+    print_int(c.x)           # 42
+  }
+}