fix(#1): remove duplicate npm ci from parallel CI steps

Woodpecker shares the workspace volume across steps. Only the install
step should run npm ci — parallel steps (lint, typecheck, test, etc.)
were each re-running npm ci concurrently, corrupting node_modules.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.woodpecker.yml

@@ -3,20 +3,17 @@ when:
 
 variables:
   - &node_image "node:22-alpine"
-  - &install_deps |
-    corepack enable
-    npm ci
 
 steps:
   install:
     image: *node_image
     commands:
-      - *install_deps
+      - corepack enable
+      - npm ci
 
   lint:
     image: *node_image
     commands:
-      - *install_deps
       - npm run lint
     depends_on:
       - install
@@ -24,7 +21,6 @@ steps:
   typecheck:
     image: *node_image
     commands:
-      - *install_deps
       - npm run typecheck
     depends_on:
       - install
@@ -32,7 +28,6 @@ steps:
   format-check:
     image: *node_image
     commands:
-      - *install_deps
       - npm run format:check
     depends_on:
       - install
@@ -47,7 +42,6 @@ steps:
   test:
     image: *node_image
     commands:
-      - *install_deps
       - npm run test:coverage
     depends_on:
       - install
@@ -55,7 +49,6 @@ steps:
   build:
     image: *node_image
     commands:
-      - *install_deps
       - npm run build
     depends_on:
       - lint
@@ -70,7 +63,6 @@ steps:
       GITEA_TOKEN:
         from_secret: gitea_token
     commands:
-      - *install_deps
       - npm run build
       - |
         echo "//git.mosaicstack.dev/api/packages/mosaic/npm/:_authToken=$$GITEA_TOKEN" > .npmrc