chore: remove dead code, legacy features, and unearned options

[richardsolomou]

What Changed

Nine commits, each self-contained. Reviewing commit by commit is much easier than reading the squashed diff.

Dead code:

• 6f824244a deletes twelve source files with no importer anywhere in the repo, plus .macroscope/ (upstream's review bot, which does not run here) and scripts/announce-connect-ga.ts (mails a GA announcement to a private-beta waitlist that RAS Code never ran).
• 922267b42 deletes four more that the removals above orphaned.
• 56036eec6 drops four @deprecated shims with no production callers.

Legacy features, all opt-in and off by default:

• ecf098a73 removes LegacySidebar.tsx, a second 3.7k-line sidebar beside Sidebar.tsx.
• 505ce3bb7 removes mobile's legacy grouped thread list, leaving the flat list that was already the default.
• dda31e7f0 removes enableLegacyTokenStreaming, which chose between streaming each assistant delta straight through and buffering it.
• d7bca5a19 removes plan mode: the composer's Build/Plan toggle, the /plan and /default slash commands, and the opencode "plan" agent. This empties mobile's Legacy settings section, so that goes too.

Options that were not earning their place (38af8a3c9):

• sidebarThreadPreviewCount and dismissedProviderUpdateNotificationKeys did nothing at all. The first was read only by LegacySidebar, so removing that sidebar orphaned it; the second has no consumer as far back as the history goes. Both still appeared in the settings summary and reset list.
• glassOpacity and appearanceContrast were sliders over CSS variables whose index.css defaults match the schema defaults exactly. fontSmoothing is now always on, which is what its default already did.
• The composer and terminal font pickers are gone. The composer already fell back to the sans preference and the terminal to the code preference, so both surfaces keep the fonts they had. Each keeps its own size through a new size-only row, so all four sizes survive.
• Confirmation prompts follow reversibility instead of a preference: deleting always asks, archiving and unpinning never do. confirmQuit stays a real preference, since quitting is not reversible and costs a relaunch.

Build:

• 3e85d6c31 stops vendoring .repos/ and fetches it on demand.

Excluding .repos/, that is 93 files and about 10k lines out.

Four things kept on purpose:

• ProviderInteractionMode stays "default" | "plan". It is persisted on threads and carried by thread.turn.start, so the event log still has to decode it. Threads stored in plan mode resolve to "default" like any other, and the next send writes that back.
• PlanAgentSelectionHeal stays and now runs unconditionally. The pickers no longer offer the opencode "plan" agent, but a selection stored before this would still dispatch.
• Providers keep reporting showInteractionModeToggle, and ProviderRegistry.refresh keeps its deprecation marker. Both are inert now, but stripping them churns the five provider adapters, which is where upstream changes land most.
• The providers struct in packages/contracts/src/settings.ts is labelled legacy but is still the source of truth mid-migration, and the flat fields above it (automaticGitFetchInterval and friends) are back-compat for old clients talking to a new server. Neither is a feature.

Why

This is a fork that cherry-picks t3code/main regularly, so the cost of keeping something is not its line count, it is how often upstream touches it. I checked that for every candidate and it drove what went in.

The dead files are dead upstream too, and most have not been touched since February to June, so deleting them costs close to nothing at pick time. Two of them, ThreadTerminalPanel.tsx and GlassSafeAreaView.tsx, were last touched by the deferred Uniwind refactor (#7327), so removing them now shrinks that pick's surface.

The legacy sidebar was the opposite: upstream changed it as recently as 2026-08-28, so every sidebar and composer pick had to be applied twice. Nothing rendered a toggle for it either. The "Settings → General → Legacy features" section that two code comments pointed at does not exist, so the only way in was hand-editing a settings blob. Legacy token streaming was the same shape.

Plan mode and mobile's grouped list are the two that did have real toggles, and both kept a lot alive behind them. The grouped list needed per-group collapse state, the collapsedProjectGroups preference, show-more paging, and sort/group menu entries the flat list ignores. Plan mode reached from the contracts schema through the composer, the slash menu, the traits pickers, and the model capability filter.

On the settings cull: every option is a permanent tax on the settings page, the reset path, the search index, and every client that has to render it. The ones removed here were either provably inert or duplicated a decision the app can just make. Dropping a client-settings key is safe for stored settings; decoding already discards keys it does not recognise.

.repos/ was 12,961 files and 126MB of working tree held as committed git subtrees, most of it material nobody reads. alchemy-effect alone carried 14MB of images, 9MB of vendored PR screenshots, and its docs website. Every clone and every worktree paid for all of it. CI never did: every workflow already sparse-checked-out !/.repos/.

Run vpr sync:repos to populate .repos/ locally. A directory left over from the subtree era has no remote to fetch from, so the sync notices the missing .git and re-clones over it.

UI Changes

The default UI does not change. Every removed surface was off by default, and I confirmed in a running app that the four CSS variables behind the removed appearance sliders resolve to exactly the values those settings defaulted to (--glass-opacity: 80%, --appearance-contrast-base: 100%, both boosts 0%).

What genuinely goes away, for people who had opted in or gone looking:

• Mobile devices with Settings → Legacy → Legacy Thread List get the flat list. The Legacy section itself is gone.
• Plan mode users lose the Build/Plan toggle and the /plan and /default commands. Threads sitting in plan mode move to default on their next send.
• Settings loses the contrast and glass sliders, the font-smoothing switch, the composer and terminal font pickers, and the three thread-confirmation switches.

Checklist

• This PR is small and focused

  It is not small. You asked for one PR covering the whole cleanup. The nine commits are each one concern and are meant to be read separately.

• I explained what changed and why

• I included before/after screenshots for any UI changes

  N/A, covered above: the default UI is unchanged and I verified the appearance variables directly.

• I included a video for animation/interaction changes

  N/A, no motion or interaction changes.

How did you test this code?

Typecheck and lint clean on every package touched. Full suites: web 3059, mobile 769, contracts 292, desktop 617, shared 388, server 3041.

Two tests needed thought rather than deletion, because stripping a flag changed what they assert:

• composerProviderState.test.tsx used agent: "plan" to check that non-effort selections survive dispatch. With the plan agent always filtered it now heals to build, so I kept the subject and moved the fixture to a different non-default selection. Its two siblings already cover agent filtering directly.
• composerSlashCommandSearch.test.ts used /default to check that an exact provider match outranks a description match, relying on "ui" appearing inside "build" in its description. I moved it to /model with a search term that keeps the same premise.

Ran the real web app against a copy of production-shaped data and drove it:

• Archiving a thread acts with no confirmation; the row leaves the list.
• Deleting prompts with "Delete thread …? This permanently clears conversation history", and Cancel leaves the thread in place.
• Unpinning acts with no confirmation, and the pin clears in the database.
• Settings → Appearance has no contrast or glass slider and no font-smoothing row. Typography shows two families and four sizes; the new size-only Prompt row drives --font-size-prompt to 18px when changed.
• Settings → General has none of the three confirmation switches, no Legacy section, no plan mode, no token-streaming entry.
• The composer footer shows model, effort, and access, with no Build/Plan toggle.

Ran the mobile app on an iOS 26 simulator after a clean native rebuild (the installed dev client predated the Expo SDK 57 bump and reported a React Native version mismatch, which is unrelated to this branch):

• The app boots and the flat thread list renders real threads, including a FAILED status and the collapsible Settled shelf.
• The thread list options menu offers only Project and Environment; the sort and group entries are gone.
• Settings has no Legacy section.

For .repos/ I ran the new sync against the real remotes rather than trusting the unit tests: clone, re-run onto the fetch path, both repos, each landing in about three seconds at the right pinned tag with effect-smol/LLMS.md present. The new stale-directory test was checked by perturbing removeExisting to confirm it fails for the intended reason.

One pre-existing failure shows up locally and is not from this branch: apps/server/src/entrypoint.test.ts (symlink resolution). I touched neither it nor its dependencies, it keys off host platform, and CI is green on a94b40cb, the base for this branch.