Sabaki: vanhemmat versiot ja versiohistoria

The first release in a while, and a big one. Alongside a handful of new features it modernizes the entire runtime — Sabaki now rides the current Electron and Node, so it's faster, more secure, and native on Apple Silicon — and picks up a proper automated test suite along the way. Huge thanks to everyone who contributed while things were quiet.
Platform & runtime
- Upgraded Electron from 13 all the way to 43, in steady one-major steps, so Sabaki now ships on a current Chromium and Node runtime with the accompanying performance, stability, and security improvements.
- Removed the deprecated @electron/remote dependency and moved main/renderer communication onto a proper IPC bridge (context menus, dialogs, theme management, and settings all go through IPC now).
- Modernized the Node toolchain (Node 24, mocha 11) and pinned the dev/CI Node version via .nvmrc to match the shipped Electron runtime.

Added
- Score-lead analysis graph — the analysis graph can now plot score lead in addition to win rate (thanks to @kevinsung, #828).
- Absolute vs. relative analysis display — the analysis heat map can show each candidate move's win rate / score lead as its cost relative to the best move (which then reads as 0), instead of the absolute value, from View → Analysis Metric or with Ctrl+Shift+V (thanks to @kevinsung, #1022, #843).
- Move-numbering options — number moves from the start of the game, the current variation, or the most recent hotspot (thanks to @kevinsung, #826).
- Editable territory in scoring/estimate mode — click empty points to manually override the estimated territory; overrides reset when you toggle a stone's life/death (thanks to @RobertChrist, #941).
- Node-specific "Add/View Comment" in the game-tree node menu, replacing the out-of-place global toggle that used to live there (thanks to @RobertChrist, #942, #940).
- More keyboard shortcuts — for variation editing (copy/cut/paste/shift/make-main), toggling good/bad move annotations, toggling the player to move, and showing the analysis graph (thanks to @MarcelGruenauer and @kevinsung, #1018, #1021).
- Downstream-variation navigation — step through downstream variations with Shift+Left / Shift+Right (thanks to @petermao, #773).
- Clearer help text in the "add engine" dialog, with concrete path and argument examples for non-technical users (thanks to @Chewt, #967, #756).
- Clean Markup now strips score lead (SBKS) alongside win rate.
- Added an "Always show game result" preference, surfacing the existing setting in the Preferences drawer (thanks to @MarcelGruenauer, #1036).
- Added the Sabaki Subtle theme to the theme directory (thanks to @RobertChrist).

Fixed
- Sabaki now quits on the first ⌘Q on macOS instead of leaving the process running in the background (#1035, #157), and Ctrl+Q now quits on Linux (thanks to @kevinsung, #1024).
- Settings reliability — every setting is now sent to the renderer at startup, fixing controls that could silently read as undefined; the Score and Autoplay preference controls work again (thanks to @kvwu, #1026); and a renderer setting shim was fixed (thanks to @TransientError, #1028).
- Score-lead graph hardening — stays visible at a score lead of 0, refreshes when you toggle the metric on an unanalysed node, and no longer chokes on non-numeric values.
- Hardened GTP analysis parsing — dialect-aware win-rate normalization and graceful skipping of malformed info segments.
- Fixed root-node branch numbering.
- Fixed theme uninstall (broken by a rimraf v6 bump).
- Fixed a false "file unreadable" error in development mode.
- Fixed a MaxListenersExceededWarning from settings-change listeners.
- Left/Right once again map to Previous/Next Variation (thanks to @petermao).

Developer & internal
- Added a Playwright end-to-end test suite for the Electron app (smoke, renderer, engine, and analysis flows), plus engine-integration tests driven by golden GTP transcripts, and wired E2E into CI (#998).
- Reformatted the codebase with Prettier 3 (with a .git-