fix(editor): allow hyperlink clicks in locked edgeless text blocks (#14829)

Fixes #14673

## Summary

When an edgeless text block is locked, `pointer-events: none` on the
inner content div (`edgeless-text-block.ts:308`) blocks all mouse
interaction — including clicking hyperlinks. Locking is intended to
prevent accidental edits, not to block navigation, so links should
remain clickable.

## Fix

Apply a `locked-content` class on the inner div when the block is locked
and not being edited, and add a targeted CSS rule restoring
`pointer-events: auto` on anchor elements within locked content.

## Context

Re-implements the fix from PR #14692 (authored by @moktamd, reverted per
@darkskygit's comment on #14673 because the original contributor had not
signed the CLA). The CLA is signed for this PR.

## Test plan

- [ ] On edgeless canvas, create a text block with a hyperlink (e.g.
`[link](https://affine.pro)`)
- [ ] Lock the block via the shape toolbar
- [ ] Hover the link → cursor shows pointer
- [ ] Click the link → navigation occurs
- [ ] Unlock and confirm editing still works as before

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

## Summary by CodeRabbit

* **Bug Fixes**
* Links within locked text blocks are now interactive and clickable with
proper visual cursor feedback.

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

blocksuite/affine/blocks/edgeless-text/src/edgeless-text-block.ts

@@ -43,6 +43,11 @@ export class EdgelessTextBlockComponent extends GfxBlockComponent<EdgelessTextBl
       font-weight: var(--edgeless-text-font-weight);
       text-align: var(--edgeless-text-text-align);
     }
+
+    .edgeless-text-block-container .locked-content a[href] {
+      pointer-events: auto;
+      cursor: pointer;
+    }
   `;
 
   private readonly _resizeObserver = new ResizeObserver(() => {
@@ -304,6 +309,7 @@ export class EdgelessTextBlockComponent extends GfxBlockComponent<EdgelessTextBl
         style=${styleMap(containerStyle)}
       >
         <div
+          class=${!editing && this.model.isLocked() ? 'locked-content' : ''}
           style=${styleMap({
             pointerEvents: editing ? 'auto' : 'none',
             userSelect: editing ? 'auto' : 'none',