feat(crafting-display): icon column with fit-to-bounds rendering

Recipe rows gain an icon column on the left (row_height-4 box,
fit-to-bounds, centered). The renderer calls widget._icon_resolver(
recipe) and renders the returned {atlas, uv} via
draw_sprite_transform when non-nil. Default resolver returns nil →
text-only layout preserved for modules that don't wire icons; modules
opt in by passing opts.icon_resolver to create() or via
set_icon_resolver after.

Module-side mapping (recipe.output.template → {atlas, uv}) is the
caller's responsibility — composition has no template-property
getter today (ADR-0001 keeps the read-side domain-free), so the
domain owner is the right place to hold the lookup.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

init.lua

@@ -250,13 +250,40 @@ function M._render_widget(widget, ctx)
 
     local cy = bounds.y + pad
     widget._render_rows = {}
+    -- v0.3.0: icon column. Reserve row_h px on the left for the icon
+    -- box (fit-to-bounds rendering); shift label by the same amount.
+    -- Resolver returning nil collapses the icon box to a placeholder
+    -- (text-only layout preserved for non-icon resolvers).
+    local icon_box  = row_h - 4
+    local label_x   = bounds.x + pad + icon_box + pad
     for i, row in ipairs(rows) do
         local color   = row.available and txt_col_full or txt_col_dim
         local label   = widget._label_resolver(row.recipe)
         local summary = widget._summary_resolver(row.recipe)
+        local icon    = widget._icon_resolver(row.recipe)
+
+        if icon ~= nil and engine and engine.render and engine.render.draw_sprite_transform then
+            local ok, tex = pcall(engine.module.load_texture,
+                                  widget.widget_id, icon.atlas)
+            if ok and tex and icon.uv then
+                local uv      = icon.uv
+                local max_uv  = (uv.w > uv.h) and uv.w or uv.h
+                local s       = icon_box / max_uv
+                local draw_x  = bounds.x + pad + (icon_box - uv.w * s) / 2
+                local draw_y  = cy + 2 + (icon_box - uv.h * s) / 2
+                engine.render.draw_sprite_transform(
+                    tex,
+                    draw_x, draw_y,
+                    0, s, s,
+                    0, 0,
+                    0xFFFFFFFF,
+                    uv.x, uv.y, uv.w, uv.h)
+            end
+        end
+
         if engine and engine.render and engine.render.draw_text then
             engine.render.draw_text(label,
-                                    bounds.x + pad, cy,
+                                    label_x, cy,
                                     theme.font_size_body, color)
             engine.render.draw_text(summary,
                                     bounds.x + bounds.w - pad - 100, cy,

manifest.lib

@@ -1 +1 @@
-{"id":"lib-core.crafting-display","version":"0.2.0","api_min":"0.1","deps":[{"id":"lib-core.crafting","version":"0.2.0"},{"id":"lib-core.panel","version":"0.4.0"},{"id":"lib-core.inventory-list","version":"0.1.0"},{"id":"lib-core.composition","version":"0.3.0"}]}
+{"id":"lib-core.crafting-display","version":"0.3.0","api_min":"0.1","deps":[{"id":"lib-core.crafting","version":"0.2.0"},{"id":"lib-core.panel","version":"0.4.0"},{"id":"lib-core.inventory-list","version":"0.1.0"},{"id":"lib-core.composition","version":"0.3.0"}]}