Docs for custom theme breakpoints

[Phil23]

Documentation for shopware/shopware#14612

[Copilot]

Pull request overview

This PR adds documentation for a new feature in Shopware 6.7.8.0 that allows developers to override responsive breakpoints in themes. The documentation explains how to configure custom breakpoint values through theme configuration fields and how to apply these values in both Twig/JS and SCSS contexts.

Changes:

• Added comprehensive guide for overriding Bootstrap breakpoints in themes
• Documented six new theme config fields (sw-breakpoint-xs through sw-breakpoint-xxl)
• Provided examples for configuring breakpoints in theme.json and applying them in SCSS

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[Copilot]

Invalid JSON syntax: Trailing commas are not allowed in JSON. Each line from 24 to 40 has a trailing comma that should be removed. JSON does not permit trailing commas after the last property in an object.

Suggested change

	"value": 0,
	},
	"sw-breakpoint-sm": {
	"value": 576,
	},
	"sw-breakpoint-md": {
	"value": 768,
	},
	"sw-breakpoint-lg": {
	"value": 992,
	},
	"sw-breakpoint-xl": {
	"value": 1200,
	},
	"sw-breakpoint-xxl": {
	"value": 1400,
	"value": 0
	},
	"sw-breakpoint-sm": {
	"value": 576
	},
	"sw-breakpoint-md": {
	"value": 768
	},
	"sw-breakpoint-lg": {
	"value": 992
	},
	"sw-breakpoint-xl": {
	"value": 1200
	},
	"sw-breakpoint-xxl": {
	"value": 1400

[Isengo1989]

LGTM - but not sure if we do have an exception here somehow, best be approved/commited by @Phil23

[Isengo1989]

Thx for the PR @Phil23 👍

Feel free to merge after the shopware/shopware PR is merged (hint of the version will suffice - we prefer this rather than forgetting to merge it after release).