feat(web): add DiscoverResultCard with reserved badge slot + anchored button

T14 of the M5a Lidarr plan. The Discover grid in M5a renders mixed
requestable / kept / requested cards from Lidarr search. Without
layout discipline the cards in a row land their titles at different
Y coordinates whenever the badge presence varies, which reads as
visual noise. DiscoverResultCard enforces:

  - Flex column with `margin-top: auto` on `.actions`, so the action
    button is anchored to the bottom of the card body regardless of
    title/subtitle wrap differences.
  - `.badge-row` always rendered with `min-height: 22px`, so the
    title baseline holds even when no Kept pill is present.

Both load-bearing CSS values use inline style attributes — jsdom's
getComputedStyle does not resolve scoped <style> blocks, so the tests
verify positioning via inline styles directly. The remaining decorative
CSS (kept-pill background = accent at 15%, flex-direction, gap) lives
in a scoped <style> block.

State -> action mapping (sentence case per FabledSword voice):
  requestable -> bg-action-primary "Request" with Plus icon
  kept        -> disabled ghost "In library" + Kept pill
  requested   -> disabled ghost "Requested"

Cover art falls back to a Lucide glyph (Disc3 / Album / Music2) when
imageUrl is absent. Adds lucide-svelte@^1.0.1 dependency.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

web/package-lock.json

@@ -8,7 +8,8 @@
       "name": "minstrel-web",
       "version": "0.0.0",
       "dependencies": {
-        "@tanstack/svelte-query": "^5.90.2"
+        "@tanstack/svelte-query": "^5.90.2",
+        "lucide-svelte": "^1.0.1"
       },
       "devDependencies": {
         "@sveltejs/adapter-static": "^3.0.6",
@@ -2637,6 +2638,15 @@
       "dev": true,
       "license": "ISC"
     },
+    "node_modules/lucide-svelte": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/lucide-svelte/-/lucide-svelte-1.0.1.tgz",
+      "integrity": "sha512-WvzZgk0pqzgda+AErLvgWxHkfg/+GgUwqKMRHvzt0IqyMdmyEDzDCk3Z+Wo/3y753oIgx8u9Q4eUbWkghFa8Jg==",
+      "license": "ISC",
+      "peerDependencies": {
+        "svelte": "^3 || ^4 || ^5.0.0-next.42"
+      }
+    },
     "node_modules/lz-string": {
       "version": "1.5.0",
       "resolved": "https://registry.npmjs.org/lz-string/-/lz-string-1.5.0.tgz",