feat(desktop): follow the focused bot in the profile-grouped sidebar

[kennysamuerto]

What

With Grouping → Profile in the all-profiles scope, the sidebar now answers "what is THIS bot doing?" passively:

• Follow the focused bot — the focused chat's profile group floats to the top of the list and is re-opened if it had been collapsed, so switching bots (roster click, tile focus) always reveals that bot's sessions without hunting for its section. default keeps its historical first spot when nothing else is focused; the rest stay alphabetical. A focused profile with no sessions changes nothing.
• Session count on group headers — each profile group shows its session count next to the label, readable while collapsed (analyst · 3-style, in the quaternary text tone so it stays out of the way of the cost/token totals).

Closes #89347

How

• $focusedSessionProfile moves from the plugin SDK (src/sdk/index.ts) into the session-states store, so the sidebar and host.state.focusedSessionProfile share one resolver — same focused-row → owner-profile ladder, behavior unchanged for SDK consumers.
• Profile-group construction is extracted from the index.tsx memo into a pure buildProfileGroups() (sidebar/profile-groups.ts) with colocated unit tests covering ranking (focused > default > alpha), normalization, legacy rows without a profile, and color stamping.
• A small effect calls setWorkspaceNodeOpen(focusedProfile, true) when focus moves while profile-grouped, reusing the existing collapse-state store.

Testing

• vitest run --project ui src/app/chat/sidebar src/sdk src/store — 1285 passed (includes 7 new tests in profile-groups.test.ts; profile-routing.test.ts mock updated for the moved atom).
• tsc -p . --noEmit clean; eslint clean on all touched files.

Notes

• The PROJECT_PREVIEW_COUNT cap on profile groups (only a handful of rows per group, click the label to scope) is untouched — happy to follow up there if there's appetite, since "few visible rows" was also raised in the issue discussion.
• For reference, the interaction model was first prototyped as a desktop plugin: Add bot-sessions — first desktop-plugin (@hermes/plugin-sdk) reference example hermes-example-plugins#12.

🤖 Generated with Claude Code

[Enough1122]

AI code review — automated review for reference; please use your judgment.

Reviewed the diff. Tidy feature: the focused-profile ranking lives in a pure, well-tested helper (seven unit cases covering normalization, ghost focus, default-first preservation, color stamping), the auto-reveal effect correctly no-ops when focus doesn't change (so a manual collapse survives same-profile refocuses), and lifting `$focusedSessionProfile` into `session-states` removes a private duplicate so the SDK host state and the sidebar read one source of truth. Header session-count badge answers the collapsed-glance question nicely.

Nit: two micro-points — (a) confirm `setWorkspaceNodeOpen(profileKey, true)` writes node state namespaced to the profile-grouping mode; if workspace open/closed state is shared across grouping modes, a project node that happens to share an id string would get expanded as a side effect; (b) in buildProfileGroups the `groups.set(key, group)` inside the loop is redundant (the Map already holds the mutated object reference).

No blocking issues found.

[kennysamuerto]

Thanks for the review! On the two nits:

(a) Node-state collision — confirmed not possible: workspace node ids are always path-derived (<repoRoot>::branch::<name> via branchLaneId, <repoRoot>::kanban, or absolute worktree paths — all contain / or ::), while profile keys are bare profile names, which can't take either form. Worth noting the two id families already cohabit in $sidebarWorkspaceNodeOpen before this PR: the profile pane's own useWorkspaceNodeOpen(group.id) in workspace-group.tsx reads the same bare profile key this effect writes, so the effect targets exactly the node the pane owns.

(b) groups.set in the loop — it wasn't redundant on the first insert (the ?? arm built a detached object that still needed to enter the map), but it did re-set existing references on every subsequent row. Restructured to an explicit create-then-set branch in 6570ba7 — clearer and skips the no-op sets. Tests and lint still green.

[kennysamuerto]

Rebased onto current main (v2026.8.27). Main had grown its own connection-qualified $focusedSessionOwner + $focusedSessionProfile pair in sdk/index.ts, which superseded the simple profile ladder this PR originally lifted. Resolution keeps this PR's single-source-of-truth shape while adopting the richer resolution: both computeds now live in store/session-states (exported), and the SDK imports them and re-exports the owner type as PluginFocusedSessionOwner — no behavior change to either feature. The sidebar keeps reading $focusedSessionProfile from the store as before.

Typecheck, lint and the desktop suite are green (7,975 passed; the only suite my rebase had broken was profile-routing.test.ts, whose session-states mock now also stubs $focusedSessionOwner).