fix navigation links, footer categories, product card structure, and social icons

- add missing cta_href to hero section and error page CTAs
- replace hardcoded footer shop links with real product categories
- restructure product cards with stretched-link pattern so category
  badges link to their collection page
- unify social icons: footer and contact page share the same default
  links from a single source in content.ex
- add search implementation plan (docs/plans/search.md, deferred)

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

docs/plans/search.md

@@ -0,0 +1,61 @@
+# Plan: Implement product search in search modal
+
+Status: Pending (after usability fixes)
+
+## Overview
+
+The search modal UI shell exists but has zero functionality — no event bindings, no backend search, no results rendering. This plan adds live search across all products.
+
+## Approach
+
+Small catalog (print-on-demand, < 100 products) — search `PreviewData.products()` in memory. No DB full-text search needed.
+
+Product maps have: `.name`, `.category`, `.description`, `.slug`, `.price`, `.image_url`, `.image_id`
+
+## Changes
+
+### 1. CartHook — add search assigns + event handler
+**File:** `lib/simpleshop_theme_web/cart_hook.ex`
+
+- Init assigns in `on_mount`: `search_results: []`, `search_query: ""`
+- Handle `"search"` event (from `phx-keyup`):
+  - Empty/blank query → assign `search_results: []`, `search_query: ""`
+  - Non-empty → filter `PreviewData.products()` by name/category/description (case-insensitive substring match), take 6, assign results
+- Handle `"close_search"` event → clear query + results + hide modal via JS
+
+### 2. shop_layout + search_modal — add search attrs and UI
+**File:** `lib/simpleshop_theme_web/components/shop_components/layout.ex`
+
+**shop_layout:**
+- Add optional attrs: `search_results` (default `[]`), `search_query` (default `""`)
+- Pass them to `<.search_modal>`
+
+**search_modal:**
+- Add `search_results` (list, default `[]`) and `search_query` (string, default `""`) attrs
+- Add `name="query"`, `phx-keyup="search"`, `phx-debounce="200"`, `value={@search_query}` to the input
+- On close button + backdrop click: also push `"close_search"` event
+- Results section below input:
+  - Each result: link to `/products/{slug}` with product name, category, formatted price
+  - "No results found" when query non-empty but no matches
+  - Hint text only shown when no query
+- Click on result: navigate to product, close modal (JS.hide + close_search event)
+
+### 3. Page templates — thread search assigns
+**All 8 files in** `lib/simpleshop_theme_web/components/page_templates/`
+
+Add two lines to each `<.shop_layout>` call:
+```
+search_results={assigns[:search_results] || []}
+search_query={assigns[:search_query] || ""}
+```
+
+Same pattern as `cart_drawer_open` and `cart_status`.
+
+## Files to modify
+1. `lib/simpleshop_theme_web/cart_hook.ex`
+2. `lib/simpleshop_theme_web/components/shop_components/layout.ex` (shop_layout + search_modal)
+3. All 8 page templates in `lib/simpleshop_theme_web/components/page_templates/`
+
+## Verification
+- Browser: open search modal on multiple pages, type queries, verify results appear and link correctly
+- `mix test` — all existing tests pass