docs(Toolbar): fix keys and add basic example

[layershifter]

Pull request checklist

• Addresses an existing issue: Fixes #0000
• Include a change request file using $ yarn change

Description of changes

This PR adds an example for children API and fixes keys in other examples.

Focus areas to test

(optional)

Microsoft Reviewers: Open in CodeFlow

[size-auditor]

Asset size changes

Size Auditor did not detect a change in bundle size for any component!

Baseline commit: ccc2e9a086d41a1674da17ad7f31d31fd84fe9a5 (build)

[msft-github-bot]

Perf Analysis

No significant results to display.

All results

Scenario	Master Ticks	PR Ticks	Status
BaseButton	735	720
BaseButton (experiments)	837	869
DefaultButton	973	962
DefaultButton (experiments)	1715	1682
DetailsRow	3055	2995
DetailsRow (fast icons)	3099	3090
DetailsRow without styles	2850	2838
DocumentCardTitle with truncation	1534	1579
MenuButton	1243	1284
MenuButton (experiments)	3114	3180
PrimaryButton	1120	1049
PrimaryButton (experiments)	1820	1790
SplitButton	2922	2789
SplitButton (experiments)	6575	6500
Stack	421	432
Stack with Intrinsic children	1008	1003
Stack with Text children	3560	3661
Text	317	325
Toggle	747	735
Toggle (experiments)	2009	1989
button	62	52

Perf Analysis (Fluent)

⚠️ 1 potential perf regressions detected

Potential regressions comparing to master

Scenario	Current PR Ticks	Baseline Ticks	Ratio	Regression Analysis
VideoMinimalPerf.default	945	855	1.11:1	analysis

Perf comparison

Status	Scenario	Fluent TPI	Fabric TPI	Ratio	Iterations	Ticks
🔧	Avatar.Fluent	0.55	0.47	1.17:1	2000	1098
🦄	Button.Fluent	0.09	0.18	0.5:1	5000	474
🔧	Checkbox.Fluent	0.73	0.38	1.92:1	1000	725
🔧	Dialog.Fluent	0.39	0.18	2.17:1	5000	1962
🔧	Dropdown.Fluent	3.54	0.44	8.05:1	1000	3541
🔧	Icon.Fluent	0.17	0.04	4.25:1	5000	831
🎯	Image.Fluent	0.07	0.09	0.78:1	5000	352
🔧	Slider.Fluent	1.55	0.41	3.78:1	1000	1549
🔧	Text.Fluent	0.08	0.02	4:1	5000	383
🦄	Tooltip.Fluent	0.12	16.34	0.01:1	5000	601

🔧 Needs work     🎯 On target     🦄 Amazing

Perf tests with no regressions

Scenario	Current PR Ticks	Baseline Ticks	Ratio
AccordionMinimalPerf.default	235	216	1.09:1
CarouselMinimalPerf.default	647	613	1.06:1
RadioGroupMinimalPerf.default	564	530	1.06:1
ChatDuplicateMessagesPerf.default	435	413	1.05:1
DividerMinimalPerf.default	962	917	1.05:1
HierarchicalTreeMinimalPerf.default	1035	985	1.05:1
InputMinimalPerf.default	1128	1070	1.05:1
Tooltip.Fluent	601	573	1.05:1
BoxMinimalPerf.default	370	355	1.04:1
MenuMinimalPerf.default	1990	1922	1.04:1
PopupMinimalPerf.default	245	235	1.04:1
ToolbarMinimalPerf.default	1117	1075	1.04:1
Avatar.Fluent	1098	1056	1.04:1
AvatarMinimalPerf.default	569	555	1.03:1
LayoutMinimalPerf.default	674	657	1.03:1
ListWith60ListItems.default	1212	1182	1.03:1
TooltipMinimalPerf.default	860	839	1.03:1
Button.Fluent	474	461	1.03:1
CheckboxMinimalPerf.default	3339	3265	1.02:1
DropdownManyItemsPerf.default	1456	1426	1.02:1
DropdownMinimalPerf.default	3536	3471	1.02:1
TreeMinimalPerf.default	1181	1154	1.02:1
Icon.Fluent	831	811	1.02:1
Slider.Fluent	1549	1521	1.02:1
Text.Fluent	383	376	1.02:1
AnimationMinimalPerf.default	637	633	1.01:1
ButtonSlotsPerf.default	629	620	1.01:1
TreeWith60ListItems.default	229	226	1.01:1
Dialog.Fluent	1962	1952	1.01:1
EmbedMinimalPerf.default	5456	5482	1:1
FlexMinimalPerf.default	283	284	1:1
GridMinimalPerf.default	825	826	1:1
HeaderSlotsPerf.default	1617	1618	1:1
LabelMinimalPerf.default	394	393	1:1
ReactionMinimalPerf.default	2492	2496	1:1
RefMinimalPerf.default	200	200	1:1
SplitButtonMinimalPerf.default	3563	3563	1:1
StatusMinimalPerf.default	625	622	1:1
TextAreaMinimalPerf.default	3136	3138	1:1
Dropdown.Fluent	3541	3532	1:1
AlertMinimalPerf.default	597	601	0.99:1
AttachmentMinimalPerf.default	917	929	0.99:1
AttachmentSlotsPerf.default	3573	3620	0.99:1
ButtonMinimalPerf.default	151	153	0.99:1
ChatMinimalPerf.default	565	570	0.99:1
ChatWithPopoverPerf.default	628	636	0.99:1
HeaderMinimalPerf.default	535	542	0.99:1
ImageMinimalPerf.default	344	348	0.99:1
ItemLayoutMinimalPerf.default	2016	2030	0.99:1
ListCommonPerf.default	1047	1059	0.99:1
ListMinimalPerf.default	438	443	0.99:1
ListNestedPerf.default	972	980	0.99:1
TableMinimalPerf.default	628	634	0.99:1
TextMinimalPerf.default	377	382	0.99:1
Checkbox.Fluent	725	731	0.99:1
Image.Fluent	352	356	0.99:1
FormMinimalPerf.default	929	948	0.98:1
ProviderMergeThemesPerf.default	1429	1452	0.98:1
SliderMinimalPerf.default	1598	1624	0.98:1
CustomToolbarPrototype.default	3666	3783	0.97:1
DialogMinimalPerf.default	1903	1978	0.96:1
LoaderMinimalPerf.default	1079	1125	0.96:1
MenuButtonMinimalPerf.default	1499	1560	0.96:1
PortalMinimalPerf.default	273	283	0.96:1
CardMinimalPerf.default	368	387	0.95:1
IconMinimalPerf.default	392	418	0.94:1
ProviderMinimalPerf.default	635	674	0.94:1
SegmentMinimalPerf.default	1062	1142	0.93:1