feat: grow memory limits, add icon/actor libraries, overhaul LSP diagnostics

Compiler and VM
- make every memory map limit dynamic and adjustable at both build time and
  runtime, including compiler tables, stacks, and every execution region
- reserve and grow tables, operand and return stacks, frame segments, and
  image-building output without relocating live code or globals
- rename i/o and string helpers consistently (puts -> put_s, putn -> put_n,
  scat -> cat_s) across compiler, runtime, examples, tests, and docs
- recast and consume values assigned to globals from inside functions
- allow fixed and const together, add typed closure returns (fn:t(...)),
  multi-include syntax (include rt, run, core;), and recurse type inference
- never infer string literals as word, anywhere, as argument, variable, or
  return type
- draft docs/BORROW.md: a borrow checker less intrusive than Rust's but more
  intelligent

LSP and editor integration
- require explicit includes and give every toolchain area its own namespace
  (rt, lsp, run, core)
- hover for built-in types, inferred types, values known at hover time, array
  and pointer lifetime/size, library names in include statements, and inferred
  lifetimes with explanations
- honor /* */ comments as documentation for variables and arguments, and stop
  misattributing section headers or trailing comments as variable hints
- stream diagnostics and cancel stale requests on change
- jump to definition and references, including cross-file
- quick fixes with automatic library import, and namespace completion

Hints and diagnostics
- render hints as blue squigglies by default, with hints on/small/off per file
- suppress magic-number hints via a preceding /* */ comment, and say so
- warn on unused arguments; allow multiple _ discards in parameters, pattern
  matching, and tagged enums, warning if a _ is actually used
- rewrite hint and comment prose in professional compiler-doc register

Libraries
- add icon.zc: run-time self-modification, find/replace syntax, type and block
  edits, and step-through inspection of locals and globals
- add actor.zc: async actors with Actor<I,O>, implicit this, spawn/recv/send,
  injected into the compiler machinery at include time rather than built in

Tooling and docs
- reorganize sources, tests, and designs into subdirectories
- unify windows entry points in tinyvm.bat and add a matching tinyvm.sh
- add --help across the toolchain
- polish the learning guide, stdlib docs, and design notes

Tests
- add accept, reject, and regression coverage across the compiler, LSP,
- runtime, icon, actors, threads, formatting, and the toolchain contracts,
  plus fuzzers and property tests

1 files changed, 63 insertions, 0 deletions

diff --git a/tests/drivers/fuzz_malformed.py b/tests/drivers/fuzz_malformed.py
new file mode 100644
index 0000000..5bf97cf
--- /dev/null
+++ b/tests/drivers/fuzz_malformed.py
@@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+"""Deterministic malformed-source differential fuzzing for compiler hosts.
+
+Usage: python3 tests/drivers/fuzz_malformed.py [native] [microcore]
+"""
+import random
+import subprocess
+import sys
+
+
+bins = sys.argv[1:] or ["bin/zy", "bin/zym"]
+if len(bins) == 1:
+    bins.append(bins[0])
+rng = random.Random(0xC0DE)
+tokens = [
+    b"fn", b"let", b"int", b"char*", b"word", b"return", b"if", b"else",
+    b"while", b"for", b"include", b"std", b";", b"{", b"}", b"(", b")",
+    b"[", b"]", b"=", b",", b".", b":", b"?", b"+", b"-", b"*", b"&",
+    b"|", b"!", b"~", b'"text"', b"'x'", b"0", b"1", b"_", b"NIF",
+    b"asm", b"unchecked", b"\x00", b"\xff", "λ".encode(),
+]
+cases = []
+for i in range(256):
+    words = [rng.choice(tokens) for _ in range(rng.randrange(1, 100))]
+    cases.append(b" ".join(words) + b"\n")
+
+# Mutate a small valid program around parser and analyzer boundaries. Keeping
+# each mutation bounded makes a failing seed easy to reproduce and minimize.
+base = b"include std;\nfn main() { let x = 1; return x; }\n"
+for _ in range(64):
+    data = bytearray(base)
+    for __ in range(rng.randrange(1, 5)):
+        at = rng.randrange(len(data))
+        if rng.randrange(2):
+            data[at:at + 1] = rng.choice(tokens)
+        else:
+            del data[at:at + 1]
+    cases.append(bytes(data))
+
+
+def run(binary, source):
+    return subprocess.run(
+        [binary], input=b"typecheck on;\n" + source, capture_output=True, timeout=3
+    )
+
+
+for i, source in enumerate(cases):
+    results = []
+    for binary in bins:
+        try:
+            result = run(binary, source)
+        except subprocess.TimeoutExpired:
+            raise SystemExit(f"{binary} timed out on malformed seed 0xC0DE case {i}: {source!r}")
+        if result.returncode < 0:
+            raise SystemExit(
+                f"{binary} crashed on malformed seed 0xC0DE case {i}: "
+                f"signal {-result.returncode}, source={source!r}, stderr={result.stderr!r}"
+            )
+        results.append((result.returncode, result.stdout, result.stderr))
+    if any(result != results[0] for result in results[1:]):
+        raise SystemExit(f"compiler hosts disagreed on malformed seed 0xC0DE case {i}: {source!r}")
+
+print(f"ok   malformed-source fuzz: {len(cases)} bounded token and byte mutations agree on {len(bins)} compiler hosts")