feat(editor): improve latex editing support (#14924)

## Summary
- support converting selected text into inline LaTeX equations
- support turning text blocks into LaTeX equation blocks
- add equation entries to editor toolbars while keeping inline equation
with text formatting actions

## Tests
- yarn tsc -b blocksuite/affine/inlines/latex/tsconfig.json
blocksuite/affine/blocks/note/tsconfig.json
blocksuite/affine/blocks/root/tsconfig.json
blocksuite/affine/rich-text/tsconfig.json
blocksuite/affine/widgets/keyboard-toolbar/tsconfig.json --pretty false
- git diff --check origin/canary...HEAD

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
  * Equation block support with conversion from existing blocks.
  * Inline LaTeX insertion added to the inline formatting toolbar.
* Equation action added to the keyboard toolbar; Equation blocks
searchable via math/equation/latex aliases.

* **Improvements**
* Inline LaTeX editor opens and syncs more reliably; selection/convert
flow preserves distinct LaTeX values when converting in reverse order.

* **Tests**
  * New e2e tests for inline LaTeX conversions and value preservation.

<!-- review_stack_entry_start -->

[![Review Change
Stack](https://storage.googleapis.com/coderabbit_public_assets/review-stack-in-coderabbit-ui.svg)](https://app.coderabbit.ai/change-stack/toeverything/AFFiNE/pull/14924)

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<!-- end of auto-generated comment: release notes by coderabbit.ai -->

tests/blocksuite/e2e/latex/inline.spec.ts

@@ -1,5 +1,12 @@
 import { expect } from '@playwright/test';
 
+import {
+  dragBetweenIndices,
+  enterPlaygroundRoom,
+  focusRichText,
+  initEmptyParagraphState,
+  waitNextFrame,
+} from '../utils/actions/index.js';
 import {
   cutByKeyboard,
   pasteByKeyboard,
@@ -15,17 +22,13 @@ import {
   type,
   undoByKeyboard,
 } from '../utils/actions/keyboard.js';
-import {
-  enterPlaygroundRoom,
-  focusRichText,
-  initEmptyParagraphState,
-} from '../utils/actions/misc.js';
 import {
   assertRichTextInlineDeltas,
   assertRichTextInlineRange,
 } from '../utils/asserts.js';
 import { ZERO_WIDTH_FOR_EMPTY_LINE } from '../utils/inline-editor.js';
 import { test } from '../utils/playwright.js';
+import { getFormatBar } from '../utils/query.js';
 
 test('add inline latex at the start of line', async ({ page }, testInfo) => {
   await enterPlaygroundRoom(page);
@@ -240,6 +243,63 @@ test('add inline latex using slash menu', async ({ page }, testInfo) => {
   expect(await latexElement.locator('.katex').innerHTML()).toBe(innerHTML);
 });
 
+test('should preserve distinct latex values when converting selections in reverse order', async ({
+  page,
+}) => {
+  await enterPlaygroundRoom(page);
+  await initEmptyParagraphState(page);
+  await focusRichText(page);
+
+  await type(page, 'a+b test a^2 test');
+
+  await dragBetweenIndices(page, [0, 9], [0, 12]);
+  const { formatBar } = getFormatBar(page);
+  await expect(formatBar).toBeVisible();
+  await formatBar.getByRole('button', { name: 'Inline equation' }).click();
+  await waitNextFrame(page);
+
+  await assertRichTextInlineDeltas(page, [
+    {
+      insert: 'a+b test ',
+    },
+    {
+      insert: ' ',
+      attributes: {
+        latex: 'a^2',
+      },
+    },
+    {
+      insert: ' test',
+    },
+  ]);
+
+  await dragBetweenIndices(page, [0, 0], [0, 3]);
+  await expect(formatBar).toBeVisible();
+  await formatBar.getByRole('button', { name: 'Inline equation' }).click();
+  await waitNextFrame(page);
+
+  await assertRichTextInlineDeltas(page, [
+    {
+      insert: ' ',
+      attributes: {
+        latex: 'a+b',
+      },
+    },
+    {
+      insert: ' test ',
+    },
+    {
+      insert: ' ',
+      attributes: {
+        latex: 'a^2',
+      },
+    },
+    {
+      insert: ' test',
+    },
+  ]);
+});
+
 test('add inline latex using markdown shortcut', async ({ page }) => {
   await enterPlaygroundRoom(page);
   await initEmptyParagraphState(page);