feat: add linkedQueryParam implementation, tests and docs

[eneajaho]

Added docs for most of the usecases:

• string
• number
• boolean
• object
• array

Added example for filtering and pagination with resource API.

Added multiple tests to test all the possible usecases.

Added 2 helper functions for easier parsing (paramToNumber, paramToBoolean), with support for defaultValue.

Here is some self-explanatory code examples:

export class MyCmp {

        readonly searchQuery = linkedQueryParam('searchQuery');
	
	// Parse a boolean query parameter
	showHidden = linkedQueryParam('showHidden', { parse: paramToBoolean({defaultValue: false}) });

	// Parse a number query parameter
	count = linkedQueryParam('count', { parse: paramToNumber({defaultValue: 0}) });

	// Parse an object query parameter
	filter = linkedQueryParam('filter', {
		parse: (value) => JSON.parse(value ?? '{}'),
		stringify: (value) => JSON.stringify(value),
	});

	// Parse an array query parameter
	selectedCategoriesIds = linkedQueryParam<string[]>('selectedCategoriesIds', {
		parse: (value) => value?.split(',').map((x) => x.trim()) ?? [],
		stringify: (value) => value.join(','),
	});

	selectCategoryId(id: string) {
           // we are working with writable signals, so we can set/update them
           this.selectedCategoriesIds.update((x) => [...x, id]);
	}
}

Playground: https://stackblitz.com/edit/stackblitz-starters-v1gtrd?file=src%2Ftodos.ts