fix(html): support iterating & Children in html for-loops

[XploitMonk0x01]

• Added reference iteration support for Children so html for-loops can work with &children style.
• Added a compile-pass macro test that uses for child in &children.

[github-actions]

Visit the preview URL for this PR (updated for commit 89df185):

https://yew-rs-api--pr4074-fix-4073-html-for-re-rngw6dvr.web.app

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[github-actions]

Benchmark - core

Yew Master

vnode           fastest       │ slowest       │ median        │ mean          │ samples │ iters
╰─ vnode_clone  2.174 ns      │ 3.425 ns      │ 2.177 ns      │ 2.226 ns      │ 100     │ 1000000000

Pull Request

vnode           fastest       │ slowest       │ median        │ mean          │ samples │ iters
╰─ vnode_clone  2.175 ns      │ 4.265 ns      │ 2.18 ns       │ 2.51 ns       │ 100     │ 1000000000

[github-actions]

Size Comparison

Details

examples	master (KB)	pull request (KB)	diff (KB)	diff (%)
async_clock	101.095	101.095	0	0.000%
boids	168.882	168.882	0	0.000%
communication_child_to_parent	94.509	94.509	0	0.000%
communication_grandchild_with_grandparent	106.351	106.351	0	0.000%
communication_grandparent_to_grandchild	102.692	102.692	0	0.000%
communication_parent_to_child	91.921	91.921	0	0.000%
contexts	106.411	106.411	0	0.000%
counter	87.231	87.231	0	0.000%
counter_functional	89.269	89.269	0	0.000%
dyn_create_destroy_apps	91.146	91.146	0	0.000%
file_upload	100.326	100.326	0	0.000%
function_delayed_input	95.241	95.241	0	0.000%
function_memory_game	174.099	174.099	0	0.000%
function_router	395.915	395.915	0	0.000%
function_todomvc	165.385	165.385	0	0.000%
futures	235.984	235.984	0	0.000%
game_of_life	105.532	105.532	0	0.000%
immutable	260.494	260.494	0	0.000%
inner_html	81.774	81.774	0	0.000%
js_callback	110.397	110.397	0	0.000%
keyed_list	180.710	180.710	0	0.000%
mount_point	85.147	85.147	0	0.000%
nested_list	114.091	114.091	0	0.000%
node_refs	92.521	92.521	0	0.000%
password_strength	1719.354	1719.354	0	0.000%
portals	93.992	93.992	0	0.000%
router	366.558	366.558	0	0.000%
suspense	114.395	114.395	0	0.000%
timer	89.369	89.369	0	0.000%
timer_functional	99.803	99.803	0	0.000%
todomvc	143.096	143.096	0	0.000%
two_apps	87.145	87.145	0	0.000%
web_worker_fib	137.045	137.045	0	0.000%
web_worker_prime	188.227	188.227	0	0.000%
webgl	83.920	83.920	0	0.000%

✅ None of the examples has changed their size significantly.

[github-actions]

Benchmark - SSR

Yew Master

Details

Benchmark	Round	Min (ms)	Max (ms)	Mean (ms)	Standard Deviation
Baseline	10	291.234	292.015	291.548	0.255
Hello World	10	473.771	495.915	479.111	6.331
Function Router	10	31960.081	32593.986	32321.347	240.890
Concurrent Task	10	1005.929	1007.770	1006.942	0.613
Many Providers	10	1050.356	1096.014	1069.084	16.141

Pull Request

Details

Benchmark	Round	Min (ms)	Max (ms)	Mean (ms)	Standard Deviation
Baseline	10	291.273	291.666	291.434	0.113
Hello World	10	496.271	501.414	498.367	1.902
Function Router	10	31439.460	32315.924	31901.678	294.461
Concurrent Task	10	1006.397	1007.769	1007.176	0.567
Many Providers	10	1080.004	1142.325	1100.705	18.303

[Madoshakalaka]

can you fix the syntax error and reference the issue.

[WorldSEnder]

This could return just self.iter() and avoid the clone of the whole Vec with more precise types, I believe.

I do note that with some self-referential tricks, the above impl for ChildrenRenderer<T> could do the same, clone just the Rc instead of the whole Vec. Being able to just take a reference to the contained Vec without carrying around the owner should be a lot simpler in this case though.