ci: optimize build pipeline to eliminate redundant builds

- validate now uses test:all directly (build already done)
- Added test:ci script for explicit CI usage
- ci.yml now builds UI deps and uses build:all
- dev-release.yml separates build and validate steps
- Reduces build count from 3-4 to 1 per release cycle

.github/workflows/ci.yml

@@ -23,10 +23,12 @@ jobs:
           node-version: '22'
 
       - name: Install dependencies
-        run: bun install --frozen-lockfile
+        run: |
+          bun install --frozen-lockfile
+          cd ui && bun install --frozen-lockfile
 
       - name: Build package
-        run: bun run build
+        run: bun run build:all
 
       - name: Validate (typecheck + lint + tests)
         run: bun run validate

.github/workflows/dev-release.yml

@@ -36,10 +36,11 @@ jobs:
           bun install --frozen-lockfile
           cd ui && bun install --frozen-lockfile
 
-      - name: Build and validate
-        run: |
-          bun run build:all
-          bun run validate
+      - name: Build
+        run: bun run build:all
+
+      - name: Validate (typecheck + lint + tests)
+        run: bun run validate
 
       - name: Bump dev version
         id: bump