feat: consolidate LK language, VM, AOT, and platform support

[lollipopkit]

Summary

This branch started by removing try/catch from the AOT coverage allowlist and grew into a broad consolidation of LK's language implementation, VM, native backend, standard library, tooling, and bare-metal targets.

The result is a substantially wider and more consistently tested language surface across the interpreter and Cranelift paths. The branch contains 732 commits and changes 506 files; the sections below describe the main outcomes rather than every individual fix.

Highlights

Language and front end

• Expanded expression-oriented control flow, pattern matching, closures, traits, structs, machine integers, defer, and first-class try/catch.
• Strengthened parsing, name resolution, import handling, type checking, builtin signatures, default/named arguments, and diagnostics.
• Extended declarative and procedural macro support, hygiene, origin tracking, expansion inspection, and LSP integration.
• Consolidated user-visible semantics for equality, ordering, display, indexing, slicing, map keys, error values, and method lookup.

VM and runtime correctness

• Reworked VM compilation and execution around verified bytecode, explicit call frames, protected regions, closures, containers, imports, and runtime callables.
• Made GC marking iterative and tightened roots for pending raises, host-held values, exports, and cross-runtime payloads.
• Added recursion/depth limits where script-shaped values could otherwise overflow the Rust stack.
• Unified behavior that previously drifted across equality, display, map-key conversion, type naming, slices, and container operations.
• Preserved first-class raised values across function, module, task, and heap boundaries.

Native backend

• Expanded the typed MIR and Cranelift pipeline across control flow, containers, dynamic values, closures, traits, globals, imports, stdlib calls, and machine-width operations.
• Added native try/catch through outlined protected regions and the setjmp trampoline.
• Hardened Tier 1 hybrid ownership and reachability so outlined try bodies cannot become invalid VM bridge targets or dangling MIR calls.
• Added MIR validation for function references, protected calls, arity, and entry-return capability.
• Added scope-drop, CSE, DCE, ABI-schema conformance, optimized-build coverage, and native container-result display.
• Kept unsupported shapes explicit: eligible helpers use the hybrid bridge, while other valid programs use the Tier 0 VM bundle.

Standard library and platforms

• Expanded and aligned the desktop standard library across IO, encoding, bytes, iterators, math, strings, filesystem, process, environment, regex, random, networking, streams, tasks, channels, and time.
• Kept browser and bare-metal module surfaces explicit, with computation-only modules available under no_std.
• Added and extended Cortex-M VM execution, AArch64 native object execution, and the x86-64 bare-metal kernel, drivers, tasks, user mode, storage, input, and display checks.

Tooling and ecosystem

• Expanded the CLI across checking, formatting, bytecode/native/object compilation, bundling, coverage, macro inspection, and package workflows.
• Extended LSP diagnostics, completion, hover, definitions, references, rename, semantic tokens, code actions, code lenses, formatting, and inlay hints.
• Updated VS Code, Zed, tree-sitter, WASM playground, examples, documentation, benchmarks, and CI scripts.

Verification

Verified locally on the current head:

• cargo test --workspace --all-features
• cargo clippy --workspace --all-targets --all-features -- -D warnings
• cargo clippy -p lk-core --no-default-features --all-targets -- -D warnings
• cargo clippy -p lkrt --no-default-features --all-targets -- -D warnings
• cargo test -p lk-core --no-default-features: 1113 passed, 1 ignored
• AOT native-lowering coverage: 76/76, empty allowlist
• VM/native repository sweep: 78 identical, 1 allowed timing divergence, 0 fallback
• Strict AOT differential suites: 13/13 and 101/101
• Hybrid compile suite: 7/7
• Optimized AOT coverage and native execution checks
• LSP latency budgets and compiler scaling budget
• WASM, Zed, MCU, and no_std build checks
• Rust and LK formatting checks

The GitHub Rust Check and Performance Gate for the current head are running.