(core) Add Support Grist page and nudge

Summary:
Adds a new Support Grist page (accessible only in grist-core), containing
options to opt in to telemetry and sponsor Grist Labs on GitHub.

A nudge is also shown in the doc menu, which can be collapsed or permanently
dismissed.

Test Plan: Browser and server tests.

Reviewers: paulfitz, dsagal

Reviewed By: paulfitz

Subscribers: jarek, dsagal

Differential Revision: https://phab.getgrist.com/D3926

app/client/models/AppModel.ts

@@ -9,6 +9,7 @@ import {urlState} from 'app/client/models/gristUrlState';
 import {Notifier} from 'app/client/models/NotifyModel';
 import {getFlavor, ProductFlavor} from 'app/client/ui/CustomThemes';
 import {buildNewSiteModal, buildUpgradeModal} from 'app/client/ui/ProductUpgrades';
+import {SupportGristNudge} from 'app/client/ui/SupportGristNudge';
 import {attachCssThemeVars, prefersDarkModeObs} from 'app/client/ui2018/cssVars';
 import {OrgUsageSummary} from 'app/common/DocUsage';
 import {Features, isLegacyPlan, Product} from 'app/common/Features';
@@ -31,7 +32,15 @@ const t = makeT('AppModel');
 // Reexported for convenience.
 export {reportError} from 'app/client/models/errors';
 
-export type PageType = "doc" | "home" | "billing" | "welcome";
+export type PageType =
+  | "doc"
+  | "home"
+  | "billing"
+  | "welcome"
+  | "account"
+  | "support-grist"
+  | "activation";
+
 const G = getBrowserGlobals('document', 'window');
 
 // TopAppModel is the part of the app model that persists across org and user switches.
@@ -107,6 +116,8 @@ export interface AppModel {
 
   behavioralPromptsManager: BehavioralPromptsManager;
 
+  supportGristNudge: SupportGristNudge;
+
   refreshOrgUsage(): Promise<void>;
   showUpgradeModal(): void;
   showNewSiteModal(): void;
@@ -253,7 +264,23 @@ export class AppModelImpl extends Disposable implements AppModel {
 
   // Get the current PageType from the URL.
   public readonly pageType: Observable<PageType> = Computed.create(this, urlState().state,
-    (use, state) => (state.doc ? "doc" : (state.billing ? "billing" : (state.welcome ? "welcome" : "home"))));
+    (_use, state) => {
+      if (state.doc) {
+        return 'doc';
+      } else if (state.billing) {
+        return 'billing';
+      } else if (state.welcome) {
+        return 'welcome';
+      } else if (state.account) {
+        return 'account';
+      } else if (state.supportGrist) {
+        return 'support-grist';
+      } else if (state.activation) {
+        return 'activation';
+      } else {
+        return 'home';
+      }
+    });
 
   public readonly needsOrg: Observable<boolean> = Computed.create(
     this, urlState().state, (use, state) => {
@@ -265,6 +292,8 @@ export class AppModelImpl extends Disposable implements AppModel {
   public readonly behavioralPromptsManager: BehavioralPromptsManager =
     BehavioralPromptsManager.create(this, this);
 
+  public readonly supportGristNudge: SupportGristNudge = SupportGristNudge.create(this, this);
+
   constructor(
     public readonly topAppModel: TopAppModel,
     public readonly currentUser: FullUser|null,

app/client/models/TelemetryModel.ts

@@ -0,0 +1,32 @@
+import {AppModel, getHomeUrl} from 'app/client/models/AppModel';
+import {TelemetryPrefs} from 'app/common/Install';
+import {InstallAPI, InstallAPIImpl, TelemetryPrefsWithSources} from 'app/common/InstallAPI';
+import {bundleChanges, Disposable, Observable} from 'grainjs';
+
+export interface TelemetryModel {
+  /** Telemetry preferences (e.g. the current telemetry level). */
+  readonly prefs: Observable<TelemetryPrefsWithSources | null>;
+  fetchTelemetryPrefs(): Promise<void>;
+  updateTelemetryPrefs(prefs: Partial<TelemetryPrefs>): Promise<void>;
+}
+
+export class TelemetryModelImpl extends Disposable implements TelemetryModel {
+  public readonly prefs: Observable<TelemetryPrefsWithSources | null> = Observable.create(this, null);
+  private readonly _installAPI: InstallAPI = new InstallAPIImpl(getHomeUrl());
+
+  constructor(_appModel: AppModel) {
+    super();
+  }
+
+  public async fetchTelemetryPrefs(): Promise<void> {
+    const prefs = await this._installAPI.getInstallPrefs();
+    bundleChanges(() => {
+      this.prefs.set(prefs.telemetry);
+    });
+  }
+
+  public async updateTelemetryPrefs(prefs: Partial<TelemetryPrefs>): Promise<void> {
+    await this._installAPI.updateInstallPrefs({telemetry: prefs});
+    await this.fetchTelemetryPrefs();
+  }
+}

app/client/models/gristUrlState.ts

@@ -156,7 +156,8 @@ export class UrlStateImpl {
    */
   public updateState(prevState: IGristUrlState, newState: IGristUrlState): IGristUrlState {
     const keepState = (newState.org || newState.ws || newState.homePage || newState.doc || isEmpty(newState) ||
-                       newState.account || newState.billing  || newState.activation || newState.welcome) ?
+                       newState.account || newState.billing  || newState.activation || newState.welcome ||
+                       newState.supportGrist) ?
       (prevState.org ? {org: prevState.org} : {}) :
       prevState;
     return {...keepState, ...newState};
@@ -186,8 +187,11 @@ export class UrlStateImpl {
     // Reload when moving to/from the Grist sign-up page.
     const signupReload = [prevState.login, newState.login].includes('signup')
       && prevState.login !== newState.login;
-    return Boolean(orgReload || accountReload || billingReload || activationReload
-      || gristConfig.errPage || docReload || welcomeReload || linkKeysReload || signupReload);
+    // Reload when moving to/from the support Grist page.
+    const supportGristReload = Boolean(prevState.supportGrist) !== Boolean(newState.supportGrist);
+    return Boolean(orgReload || accountReload || billingReload || activationReload ||
+      gristConfig.errPage || docReload || welcomeReload || linkKeysReload || signupReload ||
+      supportGristReload);
   }
 
   /**