ci(forgejo): install the .nvmrc Node before npm on the Linux runner

The first real Forgejo CI run failed because the linux-builder runner ships
Node 18.19: scripts using import.meta.dirname threw, and its older npm
reported the mobile lock as out of sync with the file: dependency on
packages/core (the lock is in sync under Node 24's npm).

bootstrap-linux-toolchain.sh gains a checksum-verified `node` mode
(24.19.0, the .nvmrc version); ci.yml (quality, build-validation,
mobile-quality) and deploy-site.yml add it to GITHUB_PATH before npm runs.

.forgejo/workflows/ci.yml

@@ -44,9 +44,14 @@ jobs:
           git checkout -q -f FETCH_HEAD
           git clean -qfdx
 
-      - name: 도구 버전
+      - name: Node (.nvmrc) 설치
+        shell: bash
         run: |
-          echo "node $(node --version) (.nvmrc $(cat .nvmrc)) / npm $(npm --version)"
+          set -euo pipefail
+          export CI_PROJECT_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/d3ro-ci"
+          . scripts/ci/bootstrap-linux-toolchain.sh node
+          dirname "$(command -v node)" >> "$GITHUB_PATH"
+          echo "node $(node --version) / npm $(npm --version)"
 
       - name: 의존성 설치
         run: npm ci
@@ -95,6 +100,15 @@ jobs:
           git checkout -q -f FETCH_HEAD
           git clean -qfdx
 
+      - name: Node (.nvmrc) 설치
+        shell: bash
+        run: |
+          set -euo pipefail
+          export CI_PROJECT_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/d3ro-ci"
+          . scripts/ci/bootstrap-linux-toolchain.sh node
+          dirname "$(command -v node)" >> "$GITHUB_PATH"
+          echo "node $(node --version) / npm $(npm --version)"
+
       - name: 의존성 설치
         run: npm ci
 
@@ -122,6 +136,15 @@ jobs:
           git checkout -q -f FETCH_HEAD
           git clean -qfdx
 
+      - name: Node (.nvmrc) 설치
+        shell: bash
+        run: |
+          set -euo pipefail
+          export CI_PROJECT_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/d3ro-ci"
+          . scripts/ci/bootstrap-linux-toolchain.sh node
+          dirname "$(command -v node)" >> "$GITHUB_PATH"
+          echo "node $(node --version) / npm $(npm --version)"
+
       - name: 의존성 설치
         run: |
           npm ci

.forgejo/workflows/deploy-site.yml

@@ -30,6 +30,14 @@ jobs:
           git checkout -q -f FETCH_HEAD
           git clean -qfdx
 
+      - name: Node (.nvmrc) 설치
+        shell: bash
+        run: |
+          set -euo pipefail
+          export CI_PROJECT_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/d3ro-ci"
+          . scripts/ci/bootstrap-linux-toolchain.sh node
+          dirname "$(command -v node)" >> "$GITHUB_PATH"
+
       - name: 모바일 릴리스 공개 경계 검사
         run: node scripts/ci/verify-mobile-release-boundary.mjs --self-test