Add visual editing, Typeshed conversion, and TDBIN benchmarks

[MelbourneDeveloper]

TLDR

Adds a source-backed visual type editor for web and VS Code, introduces function declarations and end-to-end Typeshed conversion, and expands TDBIN performance validation with optimized hot paths and a MessagePack baseline.

Details

Added

• Adds shared visual-editor controls, inspector, viewport, source editing, node creation, relationship drawing, drag/pan/zoom, auto-layout, and SVG export, then wires them into the playground and VS Code custom editor.
• Adds packaged VS Code interaction commands and an Electron harness so the installed VSIX can exercise the same canvas workflow as the browser.
• Adds function declarations with generics, async signatures, overload blocks, parameter/return edges, JSON serialization, layout, rendering, and model-builder support. Existing data-only emitters deliberately omit service functions.
• Adds a Lezer-based Typeshed converter for classes, protocols, dataclasses, TypedDicts, NamedTuples, enums, aliases, conditionals, module functions, async functions, and overloads while excluding class methods.
• Adds typediagram-typeshed for mirroring complete Typeshed checkouts into .td trees, plus --from typeshed --emit td and a Typeshed tab in the web converter.
• Adds config-driven multi-language generation and watch mode with atomic output replacement, last-good-output preservation, and recovery after invalid edits.
• Adds MessagePack to the TDBIN comparison corpus and generates both the detailed report and a reader-facing benchmark page from the measured JSON.

Changed

• Optimizes TDBIN integer-block, list, writer, and packed-word hot paths while preserving the documented byte-identical wire behavior.
• Replaces the web-only viewport implementation with the shared core editor viewport and refreshes SVG snapshots for the shared canvas styling.
• Updates documentation, API examples, converter metadata, navigation, dependencies, coverage ratchets, and the bundle-size calculation for the new parser/editor runtime.

Specifications, compatibility, and removals

• Documents the function grammar, Typeshed conversion rules, CLI workflows, and reproducible TDBIN benchmark methodology.
• No public feature is removed. The old web-local viewport code is superseded by the shared implementation.
• No breaking wire-format change is introduced. Function declarations and the Typeshed converter are additive model/API surface.

How Do The Automated Tests Prove It Works?

• Typeshed converter and CLI tests cover class/data declarations, advanced annotations, overloads, async functions, conditional duplicates, complete tree mirroring, skipped empty modules, method exclusion, and failure paths without partial output.
• Function integration tests exercise parsing, resolution, printing, JSON round trips, layout, SVG rendering, overloads, async signatures, and malformed-input recovery.
• Visual-editor unit and Playwright tests exercise field and declaration edits, creation/deletion, relationships, generic-reference recovery, node dragging, pan/zoom, layout persistence, responsive controls, and export behavior.
• VS Code tests cover the packaged command bridge, real text-document replacement, invalid-edit undo/recovery, echo suppression, external document changes, panel lifecycle, and the installed VSIX interaction flow.
• Config-generation E2E tests prove initial generation, watch regeneration, atomic multi-target writes, last-good-output retention, and recovery after invalid source.
• TDBIN benchmark fixtures feed identical values to TDBIN, Protobuf, and MessagePack; the committed generated reports expose exact sizes and Criterion medians for every corpus operation.
• Coverage thresholds and bundle-size checks are ratcheted for the expanded core, CLI, web, and VS Code paths.