feat(v0.6): project card launchers — Claude/Codex/VS Code logos + active highlight

Replace each card's "+ start claude here" with a row of three brand-logo
launcher buttons (logo + caption, touch-friendly, tooltips):

- Claude (coral burst)  → new terminal tab running `claude`
- Codex  (OpenAI mark)  → new terminal tab running `codex`
- VS Code (blue ribbon) → opens the repo in VS Code ON THE HOST

VS Code: new guarded POST /open-in-editor runs `<EDITOR_CMD> <path>` (default
`code`) on the host via execFile (no shell); path validated as an existing
absolute dir; Origin guard (CSRF) like the DELETE routes. EDITOR_CMD config added.

Active-session highlight (user request): when a project has a running Claude
session (Claude-hook status != unknown — plain shells/codex stay unknown), the
Claude logo gets a coral ring + tint, with a count badge when more than one.

New: public/icons.ts (simple-icons SVGs, fill=currentColor), src/http/editor.ts.
onOpenProject gains an optional cmd; makeProjectCard exported for tests.

Tests +16 (431 total): editor validation/launch, EDITOR_CMD config, launcher
row (3 buttons, claude/codex commands), and the active-Claude highlight + badge.
Verified: coverage >=80x4, build OK, both typechecks clean; in-browser the 3
logos render with brand colours, and POST /open-in-editor actually launched
VS Code on the host (403 no-Origin / 400 bad-path / 204 valid-dir all correct).

public/tabs.ts

@@ -87,7 +87,7 @@ export class TabApp {
     }
 
     this.projects = mountProjects(this.paneHost, {
-      onOpenProject: (repoPath, repoName) => this.openProject(repoPath, repoName),
+      onOpenProject: (repoPath, repoName, cmd) => this.openProject(repoPath, repoName, cmd),
       onEnterSession: (id) => this.openSession(id),
     })