Reworks the chat and session-sidebar render paths to cut render cascades, memory
churn, and UI jank on large sessions and big session trees. Behavior is preserved;
the changes are about *when* and *how much* the UI re-renders.
## Chat streaming
- Freeze the streaming message's parts in the bulk turn projection during streaming,
and re-inject live parts only in an isolated tail leaf, so a ~60/sec delta stream
no longer re-runs the whole-session projection or re-renders unrelated rows.
session with referential reuse of unchanged turns.
- Memoize message rows with field-aware comparators instead of reference equality.
- Replace the manual child-session polling in the task tool with the live SSE
stream + a one-shot load, removing a fetch/settle state machine.
## History loading & scroll
- Load an initial page fast, then prepend one older page in the background so the
scroll container has headroom and "load older on scroll-up" fires before the user
hits the absolute top.
- Compensate scroll synchronously (in a layout effect, before paint) for prepends —
including background prepends that don't originate from a user scroll — so the
viewport stays stable instead of judder-correcting on the next frame.
## Markdown rendering
- Render markdown synchronously *styled* on first paint (paragraphs, lists, code
cards, tables, inline code) instead of raw escaped text; the async pass then only
upgrades syntax-highlight colors. Eliminates the flash of full-width raw text.
- Load KaTeX CSS eagerly with the main bundle instead of inside the lazy markdown
chunk, avoiding a late stylesheet injection on first render.
## Sidebar
- Hoist per-row recursive tree walks out of row comparators into per-group
precomputed sets/keys; batch live-session lookups into a single map; add a
group-level memo boundary.
- Isolate rename drafts so per-keystroke typing doesn't repaint the row tree.
## Sync layer
- Add a staleness guard so a slow message fetch can't repopulate a session the user
navigated away from.
- Throw on fetch failure for authoritative loaders so a transient blip can't read as
an empty server response.
## Cleanup
- Remove dead code (unused hooks, params, duplicated inline types) surfaced while
reworking the above.
## Known issue
- A rare, purely cosmetic first-paint width flash can still appear on large sessions;
it has no behavioral or data impact and is tracked for a follow-up runtime trace.
Add proper VS Code multi-root workspace support. New sessions now start in the workspace folder the user chooses instead of always using the first folder.
The VS Code sidebar now shows one shared flat session list for the currently opened workspace folders, keeps that list synced when folders are added or removed, and excludes sessions from worktrees unless that worktree is opened as a workspace folder.
Also keep the OpenCode server process independent from a specific workspace folder so changing the selected folder does not restart or interrupt existing sessions.
Replace @remixicon/react with a shared Icon component that renders
via <use href> references to a single hidden SVG sprite. This reduces
DOM node count by replacing inline SVGs with lightweight references.
- Create Icon component with sprite injection (packages/ui/src/components/icon/)
- Migrate all 164 files from @remixicon/react to Icon component
- Auto-generate sprite data from remixicon bundle (scripts/generate-icon-sprite.mjs)
- Add bun run icons:generate to package.json
- Move @remixicon/react to devDependencies
- Add icon usage instructions to theme-system skill
bashrusakh