refactor(client): rename the provide reprojection to updateCurrentProvideInfo and privatize the id resolvers

provideInfo(id)/maybeProvideInfo(id) lost their last external caller
when the renderer host switched to the currentProvideInfo observable;
both become private (tests assert through the public projection). The
reprojection method's name now says what it does — re-derive and
publish on change — and matches the field family it maintains.

packages/client/runtime/README.md

@@ -39,5 +39,5 @@ Changing the target can change or invalidate provider-side cache reuse; this pac
 ## Known Limitations and Deferred Work
 
 - **`loader.unload` is a stub (throws not-implemented)** — the full chain (fiber dispose → registration cascade → style removal) lands with the HMR project.
-- **Scope teardown is stage-driven, single-occupant today** — the staged session follows `list.current` exactly (staging is the open signal: the event window opens ⟺ the session is on stage); a removed-while-staged session's scope survives frozen until the stage moves on, not until true observer count reaches zero. Resolution (`provideInfo()`/`binding()`/`scope()`) is pure addressing, render-safe. The staged state can widen to a multi-pane list when concurrent panes land.
+- **Scope teardown is stage-driven, single-occupant today** — the staged session follows `list.current` exactly (staging is the open signal: the event window opens ⟺ the session is on stage); a removed-while-staged session's scope survives frozen until the stage moves on, not until true observer count reaches zero. Resolution (`binding()`/`scope()`) is pure addressing, render-safe; the render layer reads the current bundle through the `currentProvideInfo` observable. The staged state can widen to a multi-pane list when concurrent panes land.
 - **Value imports of this package from plugin bundles must use the `/client` subpath** — the bare package name is not in the loader externals table and inlines a second module instance, whose private scope-tag Symbol never matches (the empty-state P0 postmortem).

packages/client/runtime/src/client/sessions/service.ts

@@ -212,7 +212,7 @@ export class SessionsService {
     // The current-provide projection follows the same current writes.
     this.list.subscribe(() => {
       this.followCurrent()
-      this.projectCurrentProvide()
+      this.updateCurrentProvideInfo()
     })
     // The runtime's own contribution comes first: useSession rides the same
     // provide channel every plugin uses (no renderer special case).
@@ -261,16 +261,17 @@ export class SessionsService {
     for (const record of this.scopes.values()) {
       record.provideInfo = this.materializeProvideInfo(record.binding)
     }
-    this.projectCurrentProvide()
+    this.updateCurrentProvideInfo()
   }
 
   /**
-   * Publish the current selection's provide bundle when it changed. Bundles
-   * are identity-stable per (scope, roster) materialization, so an identity
-   * compare is exact; synchronous notify — both call sites (list.subscribe,
-   * provide()) already sit behind their own batching or registration edges.
+   * Re-derive the current selection's provide bundle and publish it when it
+   * changed. Bundles are identity-stable per (scope, roster)
+   * materialization, so an identity compare is exact; synchronous notify —
+   * both call sites (list.subscribe, provide()) already sit behind their own
+   * batching or registration edges.
    */
-  private projectCurrentProvide(): void {
+  private updateCurrentProvideInfo(): void {
     const next = this.maybeProvideInfo(this.list.getSnapshot().current)
     if (next === this.currentProvideInfoSnapshot) return
     this.currentProvideInfoSnapshot = next
@@ -446,20 +447,16 @@ export class SessionsService {
    * {@link SessionsService.currentProvideInfo}). Pure resolution — render-safe:
    * no staging, no window side effects (StrictMode double-invokes and
    * concurrent discarded passes must stay free).
-   * @param id - session id.
-   * @returns the provide info, or undefined for a session neither listed nor already scoped.
    */
-  provideInfo(id: string): SessionProvideInfo | undefined {
+  private provideInfo(id: string): SessionProvideInfo | undefined {
     return this.resolve(id as SessionId)?.provideInfo
   }
 
   /**
    * Resolve the current-session-optional standard kit. Unknown or absent ids
    * return the static no-session projection rather than removing hook props.
-   * @param id - current session id, when selected.
-   * @returns a definite or no-session provide bundle.
    */
-  maybeProvideInfo(id: string | undefined): SessionMaybeProvideInfo {
+  private maybeProvideInfo(id: string | undefined): SessionMaybeProvideInfo {
     return (id === undefined ? undefined : this.provideInfo(id)) ?? this.maybeInfo
   }
 

packages/client/runtime/tests/sessions-service.spec.ts

@@ -79,7 +79,8 @@ describe('scope tree', () => {
     expect(scopeOf(scoped as Context)).toBe('s1')
     expect(scopeOf(b.ctx)).toBeUndefined()
     const binding = b.svc.binding(sid('s1'))
-    expect(binding?.session).toBe(b.svc.provideInfo('s1')?.hooks['session'])
+    b.svc.open(sid('s1'))
+    expect(binding?.session).toBe(b.svc.currentProvideInfo.getSnapshot().hooks['session'])
     expect(b.svc.binding(sid('s1'))).toBe(binding)
     expect(binding?.ctx).toBe(scoped)
   })
@@ -183,16 +184,17 @@ describe('current selection (migrated from ui-layout, arbitrated into the list s
 })
 
 describe('cell (render-layer session kit)', () => {
-  it('resolves an identity-stable {sessionId, session} cell; unknown ids yield undefined', async () => {
+  it('resolves an identity-stable {sessionId, session} cell through the current projection', async () => {
     const b = bench()
     await feedList(b, [{ id: 's1' }])
-    const info = b.svc.provideInfo('s1')
-    expect(info).toBeDefined()
-    expect(info?.sessionId).toBe('s1')
+    b.svc.open(sid('s1'))
+    const info = b.svc.currentProvideInfo.getSnapshot()
+    expect(info.sessionId).toBe('s1')
     // The bundle carries bare observables; hook binding happens in React.
-    expect(info?.hooks['session']).toBe(b.svc.binding(sid('s1'))?.session)
-    expect(b.svc.provideInfo('s1')).toBe(info)
-    expect(b.svc.provideInfo('ghost')).toBeUndefined()
+    expect(info.hooks['session']).toBe(b.svc.binding(sid('s1'))?.session)
+    // Re-staging the same id republishes nothing: identity holds.
+    b.svc.open(sid('s1'))
+    expect(b.svc.currentProvideInfo.getSnapshot()).toBe(info)
   })
 
   it('currentProvideInfo follows selection: absent projection ↔ definite bundle, notified on each move', async () => {
@@ -204,10 +206,14 @@ describe('cell (render-layer session kit)', () => {
     const notified = vi.fn()
     b.svc.currentProvideInfo.subscribe(notified)
     b.svc.open(sid('s1'))
-    expect(b.svc.currentProvideInfo.getSnapshot()).toBe(b.svc.provideInfo('s1'))
+    const s1Bundle = b.svc.currentProvideInfo.getSnapshot()
+    expect(s1Bundle.sessionId).toBe('s1')
+    expect(s1Bundle.hooks['session']).toBe(b.svc.binding(sid('s1'))?.session)
     expect(notified).toHaveBeenCalledTimes(1)
     b.svc.open(sid('s2'))
-    expect(b.svc.currentProvideInfo.getSnapshot()).toBe(b.svc.provideInfo('s2'))
+    const s2Bundle = b.svc.currentProvideInfo.getSnapshot()
+    expect(s2Bundle.sessionId).toBe('s2')
+    expect(s2Bundle).not.toBe(s1Bundle)
     expect(notified).toHaveBeenCalledTimes(2)
     b.svc.clear()
     await Promise.resolve() // clearSelection projects through the manager notifier
@@ -249,12 +255,11 @@ describe('cell (render-layer session kit)', () => {
     expect(notified).not.toHaveBeenCalled()
   })
 
-  it('provideInfo()/binding() are pure resolution: no staging, no deferred sweep', async () => {
+  it('binding() is pure resolution: no staging, no deferred sweep', async () => {
     const b = bench()
     await feedList(b, [{ id: 's1' }, { id: 's2' }])
     b.svc.open(sid('s1')) // staged
-    b.svc.provideInfo('s2') // resolution only — must NOT move the stage
-    b.svc.binding(sid('s2'))
+    b.svc.binding(sid('s2')) // resolution only — must NOT move the stage
     await feedList(b, [{ id: 's2' }]) // s1 removed: still staged → deferred, scope survives
     expect(b.svc.scope(sid('s1'))).toBeDefined()
   })
@@ -265,7 +270,6 @@ describe('cell (render-layer session kit)', () => {
     const historyCalls = () => b.api.calls.filter(c => c.method === 'session.history')
     // Resolution is addressing, not staging: no window pull.
     b.svc.scope(sid('s1'))
-    b.svc.provideInfo('s1')
     b.svc.binding(sid('s1'))
     expect(historyCalls()).toHaveLength(0)
     b.svc.open(sid('s1'))