chore(ai-event-client): drop unused @tanstack/ai peerDependency (#694)

ai-event-client mirrors the middleware types it needs locally and imports
nothing from @tanstack/ai, so the peer dependency only manufactured a
package-manifest cycle (@tanstack/ai already depends on ai-event-client).
Remove it along with the matching `!@tanstack/ai` Nx implicitDependencies
workaround so the build graph stays a clean DAG.

Verified: pnpm install no longer warns about cyclic workspace
dependencies; build, test:types, test:lib, and publint --strict pass, and
nx affected build is clean across all consumers.

Closes #552

Author: valeriudev

.changeset/ai-event-client-drop-peer-dep.md

@@ -0,0 +1,5 @@
+---
+'@tanstack/ai-event-client': patch
+---
+
+Drop the unused `@tanstack/ai` peerDependency. `@tanstack/ai-event-client` mirrors the middleware types it needs locally and imports nothing from `@tanstack/ai`, so the peer dep only manufactured a package-manifest cycle (`@tanstack/ai` already depends on `@tanstack/ai-event-client`). Removing it — and the matching `!@tanstack/ai` Nx `implicitDependencies` workaround — keeps the build graph a clean DAG and unblocks devtools-only consumers.

packages/ai-event-client/package.json

@@ -44,9 +44,6 @@
   "dependencies": {
     "@tanstack/devtools-event-client": "^0.4.1"
   },
-  "peerDependencies": {
-    "@tanstack/ai": "workspace:*"
-  },
   "devDependencies": {
     "@vitest/coverage-v8": "4.0.14"
   },

packages/ai-event-client/project.json

@@ -1,4 +1,3 @@
 {
-  "name": "@tanstack/ai-event-client",
-  "implicitDependencies": ["!@tanstack/ai"]
+  "name": "@tanstack/ai-event-client"
 }