Expression Page Save Fix

✨ What's Improved

Fixed a critical error that prevented saving changes on the Visual Style card within the Expression section. Users were seeing: "Could not find the 'platform_voice_rules' column of 'brand_kit_expression' in the schema cache."

The Problem

The Expression page's save function was sending fields to the database that didn't exist as columns:

• platform_voice_rules — referenced in the save payload but missing from the table
• situational_tone_guides — same issue
• visual_style_1 through visual_style_5 — individual slot columns that never existed (data is stored in a single visual_style JSONB column)

This caused every save attempt on the Visual Style card to fail silently or with an error toast.

The Fix

1. Database migration — Added the missing platform_voice_rules and situational_tone_guides columns to brand_kit_expression as JSONB with sensible defaults
2. Save logic refactor — Updated ExpressionPage.performSave() to properly serialize visual style slots 1-5 into a single visual_style JSONB object and verbal style slots into verbal_style
3. Load logic update — Updated data loading to unpack the JSONB objects back into individual slot state variables

How to Verify

1. Navigate to any Brand Kit → Expression → Visual Style
2. Add or edit content in any visual style slot
3. Save — the toast should confirm success without errors
4. Reload the page — your changes should persist