move hooks.json to plugin-root/hooks/, not under .claude-plugin/

Per https://code.claude.com/docs/en/plugins.md "Convert existing
configurations": the hooks config file goes at
`<plugin-root>/hooks/hooks.json` — sibling to the script files
under hooks/, NOT inside `.claude-plugin/`. v1.0.2 had it at
`.claude-plugin/hooks/hooks.json` (still 0 hooks loaded). v1.0.3
puts it at the actually-documented path.

Final layout:
  .claude-plugin/plugin.json
  hooks/hooks.json            ← event → command map
  hooks/hyprpanel-state.sh    ← the script

`${CLAUDE_PLUGIN_ROOT}` in `command` strings is case-sensitive and
correct.

.claude-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
 	"name": "hyprpanel-state",
-	"version": "1.0.2",
+	"version": "1.0.3",
 	"description": "Surfaces per-window Claude Code state in the Hyprland workspaces bar (HyprPanel). Wires hooks for UserPromptSubmit / PreToolUse / PostToolUse / Notification / Stop / SessionEnd that write state tokens to /tmp/hyprpanel-claude/<addr> for the bar to read. Each kitty's icon and pip indicator reflects whether claude is active (blue), waiting on input (orange ●), done (green ✔), or sleeping for a /loop ScheduleWakeup (cyan ⧗). Companion to the workspaces patch in projects/hyprpanel-dev — installed bar binary needs that patch for the visuals; this plugin only owns the hook side.",
 	"author": {
 		"name": "oleks",