docs(claude): note pnpm dev:desktop self-isolates per worktree

Clarify that desktop dev worktree isolation (renderer port + app name) is
automatic and independent of .env.worktree, which only covers backend/
frontend DB names/ports. Follow-up to MUL-3724 (#4598).

Co-authored-by: multica-agent <github@multica.ai>

CLAUDE.md

@@ -90,7 +90,7 @@ pnpm exec playwright test
 pnpm ui:add badge     # shadcn/Base UI component into packages/ui
 ```
 
-Worktrees share one PostgreSQL container and get isolated DB names/ports via `.env.worktree`. `make dev` auto-detects this. For manual setup use `make worktree-env`, `make setup-worktree`, and `make start-worktree`.
+Worktrees share one PostgreSQL container and get isolated DB names/ports via `.env.worktree`. `make dev` auto-detects this. For manual setup use `make worktree-env`, `make setup-worktree`, and `make start-worktree`. `pnpm dev:desktop` additionally self-isolates per worktree (its own renderer port + app name) automatically, independent of `.env.worktree`.
 
 CI runs Node 22, Go 1.26.1, and a `pgvector/pgvector:pg17` PostgreSQL service.