add legal page editor integration and media library polish

Legal pages (privacy, delivery, terms) now auto-populate content from
shop settings on mount, show auto-generated vs customised badges, and
have a regenerate button. Theme editor gains alt text fields for logo,
header, and icon images. Image picker in page builder now has an upload
button and alt text warning badges. Clearing unused image references
shows an orphan info flash.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

PROGRESS.md

@@ -148,7 +148,7 @@ Plans: [admin-redesign.md](docs/plans/admin-redesign.md) | [admin-font-loading.m
 | ~~99~~ | ~~Stage 3: admin CRUD — create/edit/delete pages, page settings, admin index~~ | 98 | 2.5h | done |
 | ~~100~~ | ~~Stage 4: navigation management — data-driven nav, settings storage, admin editor~~ | 99 | 3h | done |
 | ~~101~~ | ~~Stage 5: SEO + redirects — sitemap, auto-redirect on slug change, draft/published~~ | 100 | 1h | done |
-| 102 | Stage 6: polish — page templates, new block types, bulk ops | 101 | 3-4h | deferred |
+| ~~102~~ | ~~Stage 6: polish — page templates, new block types, bulk ops~~ | 101 | 3-4h | done |
 | | **Platform site** | | | |
 | 73 | Platform/marketing site — brochure, pricing, sign-up | — | TBD | planned |
 | 74 | Separation of concerns: platform site vs AGPL open source core | 73 | TBD | planned |
@@ -487,9 +487,9 @@ Admin media library at `/admin/media` with image grid, type/search/orphan filter
 See: [docs/plans/media-library.md](docs/plans/media-library.md) for full plan
 
 ### Page Editor
-**Status:** Complete — all 9 stages done, 1485 tests
+**Status:** Complete — all 9 stages + custom pages done, 1485 tests
 
-Database-driven page builder. Every page is a flat list of blocks stored as JSON — add, remove, reorder, and edit blocks on any page. One generic renderer for all pages (no page-specific render functions). Portable blocks (hero, featured_products, image_text, etc.) work on any page. Page-specific blocks (product_hero, cart_items, etc.) are restricted to their native page. Block data loaders dynamically load data based on which blocks are on the page. ETS-cached page definitions. Mobile-first admin editor with live preview, undo/redo, accessible reordering (no drag-and-drop), inline settings forms, and "reset to defaults". CSS-driven page layout (not renderer-driven).
+Database-driven page builder. Every page is a flat list of blocks stored as JSON — add, remove, reorder, and edit blocks on any page. One generic renderer for all pages (no page-specific render functions). Portable blocks (hero, featured_products, image_text, etc.) work on any page. Page-specific blocks (product_hero, cart_items, etc.) are restricted to their native page. Block data loaders dynamically load data based on which blocks are on the page. ETS-cached page definitions. Mobile-first admin editor with live preview, undo/redo, accessible reordering (no drag-and-drop), inline settings forms, and "reset to defaults". CSS-driven page layout (not renderer-driven). Custom CMS pages with 4 utility block types (spacer, divider, button/CTA, video embed), page templates (blank/content/landing) for new page creation, duplicate page action, and mobile sidebar fix for the block picker.
 
 **Stages:**
 1. ~~Foundation — data model, cache, block registry~~ ✅ (`35f96e4`)
@@ -502,6 +502,7 @@ Database-driven page builder. Every page is a flat list of blocks stored as JSON
 7b. ~~SettingsField struct + repeater field type for info_card items~~ ✅ (`6fbd654`)
 8. ~~Live page editor sidebar — collapsible sidebar on shop pages, backdrop dismiss, portable content block~~ ✅ (`a039c8d`)
 9. ~~Undo/redo + polish — history stacks, keyboard shortcuts, settings animations~~ ✅
+10. ~~Custom pages stage 6 — 4 utility block types (spacer, divider, button/CTA, video embed), page templates (blank/content/landing), duplicate page, mobile block picker fix~~ ✅
 
 **Key files created:**
 - `lib/berrypod/pages.ex` — context (CRUD + cache + load_block_data)