chore: baseline V8.10.0-dev.1 with v8_workflows type-mapping fix and trade-pro spec

- SiteForge Enterprise V8.10.0-dev.1 upstream source (210 tests)
- Fix: v8_workflows._mapped_input now reads both 类型/分类 columns so WXR
  imports keep post/product types instead of collapsing to page
- Docs: trade-pro theme port spec (R3) and implementation plan

Co-Authored-By: Claude Code <noreply@anthropic.com>

app/schema_registry.py

@@ -0,0 +1,31 @@
+"""Incremental schema migration register for SQLite single-host installations.
+
+Legacy tables are created by their existing setup functions. This new ledger
+tracks newly introduced migrations and verifies their SQL checksums. Do not
+mistake this for a completed migration of all legacy PostgreSQL structures.
+"""
+from __future__ import annotations
+import hashlib
+from datetime import datetime,timezone
+
+# Each migration has separately executable (single statement) DDL entries.
+# Never rewrite an already applied migration: add a new sequence instead.
+MIGRATIONS=(
+    ('20261022_001_p1_limits',(
+        'CREATE TABLE IF NOT EXISTS platform_limit_overrides (name TEXT PRIMARY KEY, value INTEGER NOT NULL CHECK (value > 0), updated_at TEXT NOT NULL)',
+    )),
+)
+
+def ensure(conn):
+    conn.execute('''CREATE TABLE IF NOT EXISTS schema_migrations (
+        version TEXT PRIMARY KEY, checksum TEXT NOT NULL, applied_at TEXT NOT NULL)''')
+    for version,statements in MIGRATIONS:
+        checksum=hashlib.sha256('\n'.join(statements).encode()).hexdigest()
+        row=conn.execute('SELECT checksum FROM schema_migrations WHERE version=?',(version,)).fetchone()
+        if row:
+            if row[0]!=checksum:raise RuntimeError('Schema migration checksum mismatch: '+version)
+            continue
+        # The caller owns a single transaction. DDL and ledger entry commit together.
+        for sql in statements:conn.execute(sql)
+        conn.execute('INSERT INTO schema_migrations VALUES (?,?,?)',(
+            version,checksum,datetime.now(timezone.utc).isoformat(timespec='seconds')))