webui: add tooltips for upper-right corner buttons

Fixes https://github.com/boldsoftware/sketch/issues/160

Co-Authored-By: sketch <hello@sketch.dev>
Change-ID: s7884db8812a87864k
diff --git a/webui/src/web-components/sketch-app-shell-base.ts b/webui/src/web-components/sketch-app-shell-base.ts
index 3ddc183..8e777eb 100644
--- a/webui/src/web-components/sketch-app-shell-base.ts
+++ b/webui/src/web-components/sketch-app-shell-base.ts
@@ -937,6 +937,7 @@
             ?disabled=${(this.containerState?.outstanding_llm_calls || 0) ===
               0 &&
             (this.containerState?.outstanding_tool_calls || []).length === 0}
+            title="Ask the agent to pause its work, may take a moment"
           >
             <svg
               class="w-4 h-4"
@@ -956,6 +957,7 @@
             id="endButton"
             class="bg-gray-600 hover:bg-gray-700 disabled:bg-gray-400 disabled:cursor-not-allowed disabled:opacity-70 text-white border-none px-1.5 py-1 xl:px-2.5 rounded cursor-pointer text-xs mr-1.5 flex items-center gap-1.5 transition-colors"
             @click=${this._handleEndClick}
+            title="End the session and shut down the container, may cause data loss"
           >
             <svg
               class="w-4 h-4"