feat(launcher): render detail panel content (title/desc/deps)

panels/detail.lua now renders the selected module's title, version,
author, markdown description, and per-dep status list with OK/WARN/ERR
glyphs. Dep-list order follows manifest.module::deps[] (L-Q6 load-
order, no re-sort). Whole-list bg-tint is bubbled to ctx.list_tint so
the list panel picks up a yellow/red ambient cue for warn/error
states. Hero strip remains a placeholder until L.5.

panels/detail.lua

@@ -1,36 +1,116 @@
 local M = {}
 
-local PADDING = 24
-local COLOR_BG    = 0x282828FF
-local COLOR_TEXT  = 0xE0E0E0FF
-local COLOR_DIM   = 0xA0A0A0FF
-local FONT_TITLE  = 28
-local FONT_BODY   = 14
+local PADDING       = 24
+local COLOR_BG      = 0x282828FF
+local COLOR_TEXT    = 0xE0E0E0FF
+local COLOR_DIM     = 0xA0A0A0FF
+local COLOR_OK      = 0x80C080FF
+local COLOR_WARN    = 0xE0C040FF
+local COLOR_ERR     = 0xE05040FF
+local FONT_TITLE    = 28
+local FONT_SUB      = 16
+local FONT_BODY     = 14
+local FONT_DEP      = 14
+
+local md  -- lazy-loaded markdown renderer
+
+local function ensure_md(launcher_dir)
+    if not md then md = dofile(launcher_dir .. "/markdown.lua") end
+end
+
+local function status_glyph(dep_status)
+    if dep_status == "ok"    then return "OK",   COLOR_OK   end
+    if dep_status == "warn"  then return "WARN", COLOR_WARN end
+    if dep_status == "error" then return "ERR",  COLOR_ERR  end
+    return "?", COLOR_DIM
+end
+
+local function find_entry(ctx, id)
+    if id == "news" then return nil end
+    for _, e in ipairs(ctx.module_entries) do
+        if e.id == id then return e end
+    end
+    return nil
+end
 
 function M.render(ctx)
     local p = ctx.detail_panel_rect
     engine.render.draw_rect(p.x, p.y, p.w, p.h, COLOR_BG)
 
     if not ctx.selected_entry then
-        -- Empty state: background image + hint text (L.10 ships the image).
-        if ctx.bg_texture then
-            engine.render.draw_texture(ctx.bg_texture, p.x, p.y)
-        end
+        if ctx.bg_texture then engine.render.draw_texture(ctx.bg_texture, p.x, p.y) end
         local hint = ctx.t("empty_hint")
         local w, h = engine.render.measure_text(hint, FONT_BODY)
-        engine.render.draw_text(hint,
-            p.x + (p.w - w) / 2, p.y + (p.h - h) / 2,
-            FONT_BODY, COLOR_DIM)
+        engine.render.draw_text(hint, p.x + (p.w - w) / 2, p.y + (p.h - h) / 2,
+                                FONT_BODY, COLOR_DIM)
         return
     end
 
-    -- Stub for L.4/L.5/L.6/L.7: full content lands later.
-    engine.render.draw_text(tostring(ctx.selected_entry),
-        p.x + PADDING, p.y + PADDING, FONT_TITLE, COLOR_TEXT)
+    -- News: render news.md.
+    if ctx.selected_entry == "news" then
+        ensure_md(ctx.launcher_dir)
+        local body = ctx.news_body_blocks or {}
+        md.render(body, p.x + PADDING, p.y + PADDING, p.w - 2 * PADDING, nil)
+        return
+    end
+
+    local entry = find_entry(ctx, ctx.selected_entry)
+    if not entry then return end
+    local mc = ctx.manifest_cache[entry.id] or { meta = {}, blocks = {} }
+
+    -- Carousel hero placeholder: L.5 swaps this in. For now: a strip.
+    local hero_h = 160
+    if ctx.carousel_state[entry.id] and ctx.carousel_mod then
+        -- L.5 implements this; render call lands later.
+    else
+        engine.render.draw_rect(p.x, p.y, p.w, hero_h, 0x404040FF)
+    end
+
+    local cur_y = p.y + hero_h + PADDING
+    -- Title row.
+    local title = entry.summary or entry.name or entry.id
+    engine.render.draw_text(title, p.x + PADDING, cur_y, FONT_TITLE, COLOR_TEXT)
+    local _, title_h = engine.render.measure_text(title, FONT_TITLE)
+    -- Version + author right-aligned.
+    local sub = string.format("v%s  %s", entry.version, mc.meta.author or "")
+    local sub_w, _ = engine.render.measure_text(sub, FONT_SUB)
+    engine.render.draw_text(sub, p.x + p.w - PADDING - sub_w, cur_y + 6,
+                            FONT_SUB, COLOR_DIM)
+    cur_y = cur_y + title_h + 12
+
+    -- Description (rendered MD).
+    ensure_md(ctx.launcher_dir)
+    cur_y = md.render(mc.blocks, p.x + PADDING, cur_y,
+                      p.w - 2 * PADDING, entry.id)
+
+    cur_y = cur_y + 12
+
+    -- Dep list — load-order from manifest.module per L-Q6.
+    local r = entry.status.dep_check_result
+    local dep_count = (r and r.deps and #r.deps) or 0
+    engine.render.draw_text(
+        string.format("%s (%d)", ctx.t("dependencies"), dep_count),
+        p.x + PADDING, cur_y, FONT_SUB, COLOR_TEXT)
+    cur_y = cur_y + 24
+
+    if r and r.deps then
+        for _, d in ipairs(r.deps) do
+            local glyph, col = status_glyph(d.status)
+            engine.render.draw_text(glyph, p.x + PADDING, cur_y, FONT_DEP, col)
+            engine.render.draw_text(string.format("%s  %s", d.id, d.version),
+                p.x + PADDING + 40, cur_y, FONT_DEP, COLOR_TEXT)
+            cur_y = cur_y + 20
+        end
+    end
+
+    -- Whole-list tint hint: bubble up to ctx.list_tint so panels/list.lua picks it up.
+    if r and r.kind == "error" then ctx.list_tint = "error"
+    elseif r and r.kind == "warn" then ctx.list_tint = "warn"
+    end
 end
 
 function M.handle_click(ctx, mx, my)
-    -- Stub: real hit-tests for launch button + carousel arrows in L.5/L.7.
+    -- L.5/L.7 add carousel-arrow + launch-button hit-tests.
     return false
 end