feat(v0.6): kill a session directly from the Projects grid cards

The detail view could kill sessions, but the grid card's session rows were
enter-only. Add a ✕ kill button to each card session row (stopPropagation so it
doesn't also enter the session); makeSessionRow gains an optional onKill,
makeProjectCard an optional onKillSession, and mountProjects wires it to
DELETE /live-sessions/:id followed by a refresh.

Frontend-only. projects-panel tests +1 (51): ✕ present only with the callback,
click kills the right id without entering. Verified in-browser: a card with 2
sessions dropped to 1 after clicking ✕.

public/projects.ts

@@ -174,6 +174,7 @@ function sessionDotClass(status: ClaudeStatus): string {
 function makeSessionRow(
   sess: { id: string; title?: string; status: ClaudeStatus; clientCount: number },
   onEnterSession: (id: string) => void,
+  onKill?: (id: string) => void,
 ): HTMLElement {
   const row = el('div', 'proj-session-row')
   row.setAttribute('role', 'button')
@@ -185,6 +186,19 @@ function makeSessionRow(
 
   row.append(dot, title, badge)
 
+  if (onKill) {
+    const kill = el('button', 'proj-session-kill', '✕')
+    kill.title = 'Kill this session'
+    kill.setAttribute('aria-label', 'Kill session')
+    // Don't let the kill button trigger the row's enter handler.
+    kill.addEventListener('pointerdown', (e) => e.stopPropagation())
+    kill.addEventListener('click', (e) => {
+      e.stopPropagation()
+      onKill(sess.id)
+    })
+    row.append(kill)
+  }
+
   row.addEventListener('click', () => onEnterSession(sess.id))
   row.addEventListener('keydown', (e) => {
     if (e.key === 'Enter' || e.key === ' ') {
@@ -283,6 +297,7 @@ export function makeProjectCard(
   hooks: ProjectsHooks,
   onToggleFav: (path: string) => void,
   onOpenDetail?: (path: string) => void,
+  onKillSession?: (id: string) => void,
 ): HTMLElement {
   const card = el('div', 'proj-card')
 
@@ -339,7 +354,7 @@ export function makeProjectCard(
   if (runningSessions.length > 0) {
     const sessionsList = el('div', 'proj-sessions-list')
     for (const sess of runningSessions) {
-      sessionsList.append(makeSessionRow(sess, hooks.onEnterSession))
+      sessionsList.append(makeSessionRow(sess, hooks.onEnterSession, onKillSession))
     }
     card.append(sessionsList)
   }
@@ -507,6 +522,10 @@ export function mountProjects(host: HTMLElement, hooks: ProjectsHooks): Projects
     void refresh()
   }
 
+  function killAndRefresh(id: string): void {
+    void killSession(id).then(() => void refresh())
+  }
+
   function renderGrid(): void {
     const filtered = filterProjects(allProjects, searchInput.value)
     const sorted = sortProjects(filtered, favs)
@@ -534,6 +553,7 @@ export function mountProjects(host: HTMLElement, hooks: ProjectsHooks): Projects
             renderGrid()
           },
           openDetail,
+          killAndRefresh,
         ),
       )
     }