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, 52 insertions, 0 deletions

diff --git a/tests/drivers/nav_host_test.js b/tests/drivers/nav_host_test.js
new file mode 100644
index 0000000..3ffb563
--- /dev/null
+++ b/tests/drivers/nav_host_test.js
@@ -0,0 +1,52 @@
+// verify embedded built-in navigation through the extension's vm and wasm hosts.
+// usage: node tests/drivers/nav_host_test.js vm|wasm path/to/server
+const assert = require('assert');
+const fs = require('fs');
+const path = require('path');
+const mode = process.argv[2];
+const server = path.resolve(process.argv[3]);
+const client = path.resolve(__dirname, '..', '..', 'editors', 'vscode', 'client');
+const processHost = mode === 'vm'
+    ? require(path.join(client, 'vmproc.js')).vmProcess
+    : mode === 'wasm'
+        ? require(path.join(client, 'wasmproc.js')).wasmProcess
+        : null;
+assert.ok(processHost, 'host must be vm or wasm');
+const proc = processHost(server, { log: () => {} });
+const replies = new Map();
+let inbox = Buffer.alloc(0);
+proc.stdout.on('data', chunk => {
+    inbox = Buffer.concat([inbox, chunk]);
+    while (true) {
+        const end = inbox.indexOf('\r\n\r\n');
+        if (end < 0) return;
+        const size = Number(/Content-Length:\s*(\d+)/i.exec(inbox.subarray(0, end).toString())[1]);
+        if (inbox.length < end + 4 + size) return;
+        const message = JSON.parse(inbox.subarray(end + 4, end + 4 + size).toString());
+        inbox = inbox.subarray(end + 4 + size);
+        if (message.id !== undefined) replies.set(message.id, message);
+    }
+});
+function send(message) {
+    const body = Buffer.from(JSON.stringify({ jsonrpc: '2.0', ...message }));
+    proc.stdin.write(Buffer.concat([Buffer.from(`Content-Length: ${body.length}\r\n\r\n`), body]));
+}
+const source = 'include rt; fn main() { return rt.s_to_n(b"42"); }\n';
+const needle = 's_to_n';
+const offset = source.indexOf(needle);
+const before = source.slice(0, offset);
+const position = { line: before.split('\n').length - 1, character: before.length - before.lastIndexOf('\n') - 1 };
+send({ id: 1, method: 'initialize', params: { processId: 1, capabilities: {} } });
+send({ method: 'initialized', params: {} });
+send({ method: 'textDocument/didOpen', params: { textDocument: { uri: 'file:///nav.zc', languageId: 'zc', version: 1, text: source } } });
+send({ id: 2, method: 'textDocument/definition', params: { textDocument: { uri: 'file:///nav.zc' }, position } });
+send({ id: 3, method: 'zc/source', params: { path: '/rt.zc' } });
+send({ method: 'exit' });
+const location = replies.get(2)?.result?.[0];
+assert.ok(location, 's_to_n has a definition');
+assert.strictEqual(location.uri, 'tinyvm:/rt.zc');
+const runtime = replies.get(3)?.result;
+assert.strictEqual(runtime, fs.readFileSync(path.resolve(__dirname, '..', '..', 'src', 'runtime', 'rt.zc'), 'utf8'));
+const line = runtime.split('\n')[location.range.start.line];
+assert.strictEqual(line.slice(location.range.start.character, location.range.end.character), needle);
+console.log(`ok   ${mode} host opens the embedded runtime source for s_to_n`);