FSE: Add entity editor to post content block

[noahtallen]

Description

Allows the user to view and edit the content of a post content block. The post content block will use whatever post ID / post type is set via block context.

How has this been tested?

Locally in edit site. To test yourself:

1. checkout locally
2. make sure you have a template with the post content block in it. (i.e. single or index)
3. select a page from the left-most header dropdown menu
4. Select that template from the right-most header dropdown menu
5. The post content block should load with the content of the page
6. If you edit the page content, the sidebar will say that the page needs to be saved.

Screenshots

Types of changes

New feature/enhancement

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• I've updated all React Native files affected by any refactorings/renamings in this PR.

[github-actions]

Size Change: +27 B (0%)

Total Size: 1.11 MB

Filename	Size	Change
build/block-editor/index.js	105 kB	+2 B (0%)
build/block-library/index.js	119 kB	+13 B (0%)
build/blocks/index.js	48.1 kB	-2 B (0%)
build/core-data/index.js	11.4 kB	+22 B (0%)
build/edit-post/index.js	302 kB	+1 B
build/edit-site/index.js	12.8 kB	-2 B (0%)
build/editor/index.js	44.3 kB	-1 B
build/keyboard-shortcuts/index.js	2.51 kB	-2 B (0%)
build/nux/index.js	3.4 kB	-2 B (0%)
build/rich-text/index.js	14.8 kB	-2 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
build/a11y/index.js	1.02 kB	0 B
build/annotations/index.js	3.62 kB	0 B
build/api-fetch/index.js	3.39 kB	0 B
build/autop/index.js	2.83 kB	0 B
build/blob/index.js	620 B	0 B
build/block-directory/index.js	6.93 kB	0 B
build/block-directory/style-rtl.css	790 B	0 B
build/block-directory/style.css	791 B	0 B
build/block-editor/style-rtl.css	10.8 kB	0 B
build/block-editor/style.css	10.8 kB	0 B
build/block-library/editor-rtl.css	7.22 kB	0 B
build/block-library/editor.css	7.22 kB	0 B
build/block-library/style-rtl.css	7.48 kB	0 B
build/block-library/style.css	7.48 kB	0 B
build/block-library/theme-rtl.css	683 B	0 B
build/block-library/theme.css	685 B	0 B
build/block-serialization-default-parser/index.js	1.88 kB	0 B
build/block-serialization-spec-parser/index.js	3.1 kB	0 B
build/components/index.js	182 kB	0 B
build/components/style-rtl.css	17.1 kB	0 B
build/components/style.css	17.1 kB	0 B
build/compose/index.js	6.68 kB	0 B
build/data-controls/index.js	1.29 kB	0 B
build/data/index.js	8.42 kB	0 B
build/date/index.js	5.47 kB	0 B
build/deprecated/index.js	772 B	0 B
build/dom-ready/index.js	568 B	0 B
build/dom/index.js	3.11 kB	0 B
build/edit-navigation/index.js	6.6 kB	0 B
build/edit-navigation/style-rtl.css	857 B	0 B
build/edit-navigation/style.css	856 B	0 B
build/edit-post/style-rtl.css	12.2 kB	0 B
build/edit-post/style.css	12.2 kB	0 B
build/edit-site/style-rtl.css	5.22 kB	0 B
build/edit-site/style.css	5.22 kB	0 B
build/edit-widgets/index.js	7.73 kB	0 B
build/edit-widgets/style-rtl.css	4.59 kB	0 B
build/edit-widgets/style.css	4.59 kB	0 B
build/editor/editor-styles-rtl.css	425 B	0 B
build/editor/editor-styles.css	428 B	0 B
build/editor/style-rtl.css	5.07 kB	0 B
build/editor/style.css	5.08 kB	0 B
build/element/index.js	4.65 kB	0 B
build/escape-html/index.js	733 B	0 B
build/format-library/index.js	7.64 kB	0 B
build/format-library/style-rtl.css	502 B	0 B
build/format-library/style.css	502 B	0 B
build/hooks/index.js	2.13 kB	0 B
build/html-entities/index.js	622 B	0 B
build/i18n/index.js	3.56 kB	0 B
build/is-shallow-equal/index.js	711 B	0 B
build/keycodes/index.js	1.94 kB	0 B
build/list-reusable-blocks/index.js	3.13 kB	0 B
build/list-reusable-blocks/style-rtl.css	226 B	0 B
build/list-reusable-blocks/style.css	226 B	0 B
build/media-utils/index.js	5.29 kB	0 B
build/notices/index.js	1.79 kB	0 B
build/nux/style-rtl.css	616 B	0 B
build/nux/style.css	613 B	0 B
build/plugins/index.js	2.56 kB	0 B
build/primitives/index.js	1.5 kB	0 B
build/priority-queue/index.js	789 B	0 B
build/redux-routine/index.js	2.85 kB	0 B
build/server-side-render/index.js	2.68 kB	0 B
build/shortcode/index.js	1.7 kB	0 B
build/token-list/index.js	1.28 kB	0 B
build/url/index.js	4.02 kB	0 B
build/viewport/index.js	1.84 kB	0 B
build/warning/index.js	1.14 kB	0 B
build/wordcount/index.js	1.17 kB	0 B

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[epiqueras]

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