feat(mindspace): add page quota grace write and local delivery guardrails.

Centralize page HTML quota checks with grace-write semantics across page
services and workspace tools, keep localhost MindSpace links clickable in
chat display, and expand Page Data/static-page skill plus local dev docs
for quota, delivery URLs, and native Aider/OpenHands tooling.

Co-authored-by: Cursor <cursoragent@cursor.com>

mindspace-publications.mjs

@@ -21,6 +21,7 @@ import {
   inferWorkspaceHtmlRelativePath,
 } from './mindspace-html-download-links.mjs';
 import { createImgproxySigner } from './imgproxy-signer.mjs';
+import { assertPageWriteQuota } from './mindspace-space-quota.mjs';
 
 const SCANNER_VERSION = 'mindspace-content-v1';
 const PRIVATE_ASSET_DOWNLOAD_URL_PATTERN =
@@ -723,15 +724,10 @@ export function createPublicationService(pool, options = {}) {
          WHERE id = ? AND user_id = ? FOR UPDATE`,
         [page.space_id, userId],
       );
-      const available =
-        Number(spaces[0]?.quota_bytes ?? 0) -
-        Number(spaces[0]?.used_bytes ?? 0) -
-        Number(spaces[0]?.reserved_bytes ?? 0);
-      if (available < htmlBytes) {
-        throw publicationError('剩余空间不足', 'quota_exceeded', {
-          requiredBytes: htmlBytes,
-          availableBytes: Math.max(0, available),
-        });
+      try {
+        assertPageWriteQuota(spaces[0], htmlBytes);
+      } catch (error) {
+        throw publicationError(error.message, error.code ?? 'quota_exceeded', error.details);
       }
       const [publicationUsage] = await conn.query(
         `SELECT COUNT(DISTINCT page_id) AS public_page_used,