feat(harmonyos): replace the sidebar source switcher with workspaces

[wgqqqqq]

Summary

The HarmonyOS sidebar asked the user to pick a conversation source — Local or Remote — before showing them anything. That is an implementation detail: where a session runs is not how anyone looks for it, and the switcher cost a permanent row of chrome to express it.

Conversations and workspaces now share one scroll. They are different kinds of thing (a timeline and a set of places), so they stack rather than compete for the same pane, and neither carries a label saying which machine it runs on.

Verifying the new sidebar on a device turned up three follow-ons that are folded in here: the workspace section's "connect a desktop" row did not connect, a SymbolGlyph sizing trap that had been quietly pulling icons off centre across the app, and a transcript that stacked a reasoning card above the tools it drove instead of folding the two together.

Changes

Sidebar workspaces

• Drop ConversationSource and ConversationSourceSwitcher. AppRouteContract.conversationSource / routeForConversationSource become isRemoteRoute / remoteSurfaceDestination. isRemoteRoute is stated as the complement of isGeneralComposerRoute so the two predicates cannot drift apart — a route is one or the other, never both. remoteSurfaceDestination resumes an in-flight remote session rather than dropping the user on a picker they did not ask for.
• New SidebarWorkspaceSection, reaching the sidebar through a @BuilderParam slot. The sidebar has no business knowing about remote state, so the host wires it.
• Cap the conversation list at six rows behind an overflow row. The shared scroll means the list can no longer take every pixel it wants; six leaves the workspace section visible on a phone without hunting for it.
• Fade rows out under the floating footer via a new page_bg_fade token (PAGE_BG at zero alpha, defined in both the base and dark palettes). Without it a workspace row mid-scroll is visually sliced by the chat button sitting on top of it.

Make the connect-a-desktop row connect

• The row was wired to onSidebar.enterCode, which only moves the visible surface to Remote. Offline that resolves to AppRoute.RemoteHome, whose wide-layout detail pane is RemoteSurfaceHost in placeholder mode — a header and two lines of status text, no control. So the row named the last-known machine and then did nothing, and a second press returned early on the isRemoteRoute guard. RemoteSurfaceEntryPolicy already states that reaching the remote surface and asking to pair are different commands and must not share an entry point; the row now uses onSidebar.connectDesktop, which opens the connect sheet. The section header's + shares that event and is relabelled by the connection it adds, since the phone cannot create a workspace.
• Drop workspace entries with no path. syncRemotePageSummary seeds the current workspace with the placeholder name 「未连接」 and an empty path, and the projection turned any named current workspace into an entry. On the Remote surface that never showed (you only got there connected); in the sidebar it is on screen from launch, so a reconnecting phone listed a folder called 「未连接」 that opens nothing.

SymbolGlyph sizing

The connect sheet's back arrow sat visibly left of its round button. Probing on a device established why, and the same defect turned out to be spread across the app.

SymbolGlyph draws its ink left-anchored inside any box forced wider than the glyph's natural advance box; vertically it stays centred, so only the horizontal axis is affected, and a box forced smaller makes the glyph overflow rather than scale. Most symbols have a square advance box of fontSize * 1.013, but chevron_left and chevron_right are only fontSize * 0.507 wide — so every .width(N).height(N) on a chevron shifted it left by (N - fontSize * 0.507) / 2.

Of 96 SymbolGlyph call sites, 58 forced a size. They were fixed by the role that forced size was playing:

• Glyphs inside a fixed-size centring Stack or circular Button (9 sites): the forced box overrode the container's centring, by up to 4.5vp. Dropping the size lets the container centre the natural box.
• Trailing disclosure chevrons in list rows (7 sites): the forced 16–18vp box left ~10vp of dead space between the arrow and the row's right padding, so arrows never lined up with the card edge.
• Collapse indicators that swap chevron_right / chevron_down (3 sites): these keep a fixed slot — it is what stops the label jumping between states — but the slot moves to a wrapping Stack and the glyph inside goes unsized, matching the idiom already in SubagentTaskCard.
• Leading icon slots in list rows are deliberately left alone. Because ink is left-anchored, the shared forced width is exactly what keeps icon and text left edges aligned down a column of rows whose fontSize values differ.

AGENTS.md gains the measured rule. The bullet it replaces told authors to "give the glyph its visual size", which is what produced the bug in the first place.

Reasoning folds into the tool summary it drove

A transcript reads think → act → think → act, but the app rendered a single 「已思考」 sitting on top of 「已运行 4 个工具」 for a message whose items alternate.

structuredGroups buffers a maximal run of thinking entries and settled tools into one activity group, and ActivityGroup rendered every thinking part in that group above every tool in it. A run is broken only by a non-foldable entry — assistant text, a subagent card, or a live/failed/pending tool — so a silent chain of reasoning and tool calls collapses into one group and the later reasoning was hoisted over tools that had already finished when the model wrote it.

Reasoning and the tools it drove are one stretch of work, so they now fold behind a single summary row rather than standing as two cards:

• ToolStatusList takes the group's thinking parts and weaves them among its tool rows. Collapsed shows only 「已运行 N 个工具」; expanding reveals thinking and tool rows in transcript order. A lone tool has no summary to unfold, so its reasoning stays on screen rather than being lost.
• ActivityGroupPolicy states the placement rules. mergeThinkingParts keeps one header for an uninterrupted stretch of reasoning while pinning blocks on either side of a tool call to where they happened; weaveRows never places thinking above a summary row, which is the fold's own header.
• Flush buffered tools before pushing a group, so a failed or live tool held in the buffer cannot render below an activity group that came after it.

ToolStatusList also built its collapsed summary detail, operation labels, Todo/Task fallbacks, and failure suffix from Chinese string literals while the rest of the component already used RemoteI18n. Those move into the message table; the component now has no user-visible literals left.

Test plan

The documented local verification loop from AGENTS.md passes:

"$HVIGORW" --mode module -p product=default -p module=entry@default assembleHap --no-daemon
"$HVIGORW" --mode module -p module=entry@default -p ohos.test.type=LocalTest test --no-daemon
pnpm run theme:color-audit:all

ConversationPresentationUnit.test.ets, RemoteControllersUnit.test.ets, and DeviceSmoke.test.ets are updated for the route-contract rename and the removed switcher. The color audit reports no new near pairs.

Installed on a physical HarmonyOS device (wide layout, dark theme) and confirmed on screen:

• The source switcher is gone; 最近对话 and 工作区 stack in one scroll, and the workspace section shows the offline state with the "connect a desktop" row.
• The connect-a-desktop row opens the connect sheet, and no 「未连接」 placeholder folder is listed on a reconnecting phone.
• Icon geometry measured from device screenshots rather than eyeballed: the settings close button's ink centre is now 0.32vp from the circle centre (this class of site was ~7vp off before); the model row's trailing chevron leaves an 18.6vp right gap against the row's 18vp padding (~29vp before); and a thinking block's label starts at the same x in both collapsed and expanded states, so the slot did not collapse.

The fold was checked on the same real message that showed the defect. It previously rendered 已思考 above 已运行 4 个工具; it now renders 已运行 4 个工具 alone, and expanding that row reads 已思考 / GetToolSpec / GetToolSpec / 已思考 / 运行命令 / 运行命令 · gh auth status 2>&1; gh api … / 已思考 — transcript order, with the reasoning text intact when a block inside the fold is opened. No message key leaks into the UI.

Not yet exercised on device: the conversation-list overflow row (needs more than six conversations) and the connected-workspace state.