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

22 files changed, 132 insertions, 0 deletions

diff --git a/tests/icon/accept/bound_global.expected b/tests/icon/accept/bound_global.expected
new file mode 100644
index 0000000..938d790
--- /dev/null
+++ b/tests/icon/accept/bound_global.expected
@@ -0,0 +1 @@
+1 10 10
diff --git a/tests/icon/accept/bound_global.zc b/tests/icon/accept/bound_global.zc
new file mode 100644
index 0000000..f49a76b
--- /dev/null
+++ b/tests/icon/accept/bound_global.zc
@@ -0,0 +1,13 @@
+include rt;
+include run;
+include icon;
+int counter = 6;
+fn main() {
+	let q = run.tokens("counter += 4; return counter;");
+	let frame = icon.begin(q);
+	rt.put_n(icon.bind_global(frame, "counter")); rt.put_c(' ');
+	icon.resume(frame, 3);
+	rt.put_n(counter); rt.put_c(' '); rt.put_n(icon.result(frame)); rt.put_c(10);
+	icon.close(d*frame);
+	return 0;
+}
diff --git a/tests/icon/accept/branch_edit.expected b/tests/icon/accept/branch_edit.expected
new file mode 100644
index 0000000..9c1b765
--- /dev/null
+++ b/tests/icon/accept/branch_edit.expected
@@ -0,0 +1 @@
+9 7
diff --git a/tests/icon/accept/branch_edit.zc b/tests/icon/accept/branch_edit.zc
new file mode 100644
index 0000000..b360a6a
--- /dev/null
+++ b/tests/icon/accept/branch_edit.zc
@@ -0,0 +1,11 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let q = run.tokens("if (1) { return 7; } else { return 9; }");
+	let pattern = run.tokens("if ($expr:condition) { $stmt:yes } else { $stmt:no }");
+	let replacement = run.tokens("if ($condition) { $no } else { $yes }");
+	let edited = icon.rewrite(q, pattern, replacement);
+	rt.put_n(run.eval(edited)); rt.put_c(' '); rt.put_n(run.eval(q)); rt.put_c(10);
+	return 0;
+}
diff --git a/tests/icon/accept/calculate.expected b/tests/icon/accept/calculate.expected
new file mode 100644
index 0000000..d81cc07
--- /dev/null
+++ b/tests/icon/accept/calculate.expected
@@ -0,0 +1 @@
+42
diff --git a/tests/icon/accept/calculate.zc b/tests/icon/accept/calculate.zc
new file mode 100644
index 0000000..77ba7ea
--- /dev/null
+++ b/tests/icon/accept/calculate.zc
@@ -0,0 +1,8 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let q = run.tokens("(3 + 4) * (8 - 2)");
+	rt.put_n(icon.calculate(q, 0, q[0])); rt.put_c(10);
+	return 0;
+}
diff --git a/tests/icon/accept/edit_declaration.expected b/tests/icon/accept/edit_declaration.expected
new file mode 100644
index 0000000..f599e28
--- /dev/null
+++ b/tests/icon/accept/edit_declaration.expected
@@ -0,0 +1 @@
+10
diff --git a/tests/icon/accept/edit_declaration.zc b/tests/icon/accept/edit_declaration.zc
new file mode 100644
index 0000000..59b7eb8
--- /dev/null
+++ b/tests/icon/accept/edit_declaration.zc
@@ -0,0 +1,12 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let q = run.tokens("int discarded = 8; int n = 5; return n * 2;");
+	let a = icon.undeclare(q, "discarded");
+	let type = run.tokens("i32"), block = run.tokens("int extra = 2;");
+	let b = icon.change_type(a, "n", type);
+	let c = icon.insert_block(b, 0, block);
+	rt.put_n(run.eval(c)); rt.put_c(10);
+	return 0;
+}
diff --git a/tests/icon/accept/function_step.expected b/tests/icon/accept/function_step.expected
new file mode 100644
index 0000000..c2096ed
--- /dev/null
+++ b/tests/icon/accept/function_step.expected
@@ -0,0 +1 @@
+13 5
diff --git a/tests/icon/accept/function_step.zc b/tests/icon/accept/function_step.zc
new file mode 100644
index 0000000..6bdf344
--- /dev/null
+++ b/tests/icon/accept/function_step.zc
@@ -0,0 +1,12 @@
+include rt;
+include run;
+include icon;
+int target(int value) { int n = value * 2; return n + 1; }
+fn main() {
+	let frame = icon.begin_function(target);
+	icon.set_local(frame, "value", 6);
+	icon.resume(frame, 8);
+	rt.put_n(icon.result(frame)); rt.put_c(' '); rt.put_n(target(2)); rt.put_c(10);
+	icon.close(d*frame);
+	return 0;
+}
diff --git a/tests/icon/accept/literal_replace.expected b/tests/icon/accept/literal_replace.expected
new file mode 100644
index 0000000..9c67935
--- /dev/null
+++ b/tests/icon/accept/literal_replace.expected
@@ -0,0 +1 @@
+1 4
diff --git a/tests/icon/accept/literal_replace.zc b/tests/icon/accept/literal_replace.zc
new file mode 100644
index 0000000..70f7527
--- /dev/null
+++ b/tests/icon/accept/literal_replace.zc
@@ -0,0 +1,9 @@
+include rt;
+include run;
+include icon;
+int addition() { return 7 + 3; }
+fn main() {
+	let changed = icon.find_replace(addition, ${ $int + $int }, ${ $int - $int });
+	rt.put_n(changed); rt.put_c(' '); rt.put_n(addition()); rt.put_c(10);
+	return 0;
+}
diff --git a/tests/icon/accept/loop_step.expected b/tests/icon/accept/loop_step.expected
new file mode 100644
index 0000000..15d5109
--- /dev/null
+++ b/tests/icon/accept/loop_step.expected
@@ -0,0 +1 @@
+1 8 1
diff --git a/tests/icon/accept/loop_step.zc b/tests/icon/accept/loop_step.zc
new file mode 100644
index 0000000..7a0368e
--- /dev/null
+++ b/tests/icon/accept/loop_step.zc
@@ -0,0 +1,12 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let q = run.tokens("int n = 0; while (n < limit) { n += 1; } if (n == 4) { n *= 2; } else { n = 99; } return n;");
+	let frame = icon.begin(q);
+	icon.set_global(frame, "limit", 4);
+	icon.resume(frame, 3); rt.put_n(icon.local(frame, "n")); rt.put_c(' ');
+	icon.resume(frame, 30); rt.put_n(icon.result(frame)); rt.put_c(' '); rt.put_n(icon.state(frame)); rt.put_c(10);
+	icon.close(d*frame);
+	return 0;
+}
diff --git a/tests/icon/accept/named_capture.expected b/tests/icon/accept/named_capture.expected
new file mode 100644
index 0000000..45a4fb7
--- /dev/null
+++ b/tests/icon/accept/named_capture.expected
@@ -0,0 +1 @@
+8
diff --git a/tests/icon/accept/named_capture.zc b/tests/icon/accept/named_capture.zc
new file mode 100644
index 0000000..258004d
--- /dev/null
+++ b/tests/icon/accept/named_capture.zc
@@ -0,0 +1,10 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let q = run.tokens("return (2 + 5) * (2 + 5);");
+	let p = run.tokens("$expr:x * $expr:x"), r = run.tokens("$x + 1");
+	let changed = icon.rewrite(q, p, r);
+	rt.put_n(run.eval(changed)); rt.put_c(10);
+	return 0;
+}
diff --git a/tests/icon/accept/nested_declaration.expected b/tests/icon/accept/nested_declaration.expected
new file mode 100644
index 0000000..7ed6ff8
--- /dev/null
+++ b/tests/icon/accept/nested_declaration.expected
@@ -0,0 +1 @@
+5
diff --git a/tests/icon/accept/nested_declaration.zc b/tests/icon/accept/nested_declaration.zc
new file mode 100644
index 0000000..9b360e8
--- /dev/null
+++ b/tests/icon/accept/nested_declaration.zc
@@ -0,0 +1,11 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let q = run.tokens("int n = 2; { int unused = 9; int added = 3; n += added; } return n;");
+	let type = run.tokens("i32");
+	let a = icon.undeclare(q, "unused");
+	let b = icon.change_type(a, "added", type);
+	rt.put_n(run.eval(b)); rt.put_c(10);
+	return 0;
+}
diff --git a/tests/icon/accept/step.expected b/tests/icon/accept/step.expected
new file mode 100644
index 0000000..a370d71
--- /dev/null
+++ b/tests/icon/accept/step.expected
@@ -0,0 +1 @@
+4 12 14
diff --git a/tests/icon/accept/step.zc b/tests/icon/accept/step.zc
new file mode 100644
index 0000000..d394e1e
--- /dev/null
+++ b/tests/icon/accept/step.zc
@@ -0,0 +1,12 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let q = run.tokens("int n = 4; n = n * 3; return n + bias;");
+	let frame = icon.begin(q);
+	icon.set_global(frame, "bias", 2);
+	icon.step(frame); rt.put_n(icon.local(frame, "n")); rt.put_c(' ');
+	icon.step(frame); rt.put_n(icon.local(frame, "n")); rt.put_c(' ');
+	icon.step(frame); rt.put_n(icon.result(frame)); rt.put_c(10);
+	return 0;
+}
diff --git a/tests/icon/accept/token_replace.expected b/tests/icon/accept/token_replace.expected
new file mode 100644
index 0000000..8351c19
--- /dev/null
+++ b/tests/icon/accept/token_replace.expected
@@ -0,0 +1 @@
+14
diff --git a/tests/icon/accept/token_replace.zc b/tests/icon/accept/token_replace.zc
new file mode 100644
index 0000000..bf80548
--- /dev/null
+++ b/tests/icon/accept/token_replace.zc
@@ -0,0 +1,11 @@
+include rt;
+include run;
+include icon;
+fn main() {
+	let source = run.tokens("return (9 + 2) * 3;");
+	let pattern = run.tokens("$expr:left * $int:right");
+	let replacement = run.tokens("$left + $right");
+	let edited = icon.rewrite(source, pattern, replacement);
+	rt.put_n(run.eval(edited)); rt.put_c(10);
+	return 0;
+}