chore: Do not run CI jobs if "NoCI" flag is set

- Avoids costly overhead for idle PRs where the CI results don't add any
  value.

Author: ximinez

.github/workflows/clang-format.yml

@@ -4,6 +4,7 @@ on: [push, pull_request]
 
 jobs:
   check:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     runs-on: ubuntu-24.04
     env:
       CLANG_VERSION: 18

.github/workflows/doxygen.yml

@@ -11,6 +11,7 @@ concurrency:
 
 jobs:
   job:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     runs-on: ubuntu-latest
     permissions:
       contents: write

.github/workflows/levelization.yml

@@ -4,6 +4,7 @@ on: [push, pull_request]
 
 jobs:
   check:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     runs-on: ubuntu-latest
     env:
       CLANG_VERSION: 10

.github/workflows/libxrpl.yml

@@ -14,6 +14,7 @@ concurrency:
 
 jobs:
   publish:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     name: Publish libXRPL
     outputs:
       outcome: ${{ steps.upload.outputs.outcome }}

.github/workflows/macos.yml

@@ -18,6 +18,7 @@ concurrency:
 jobs:
 
   test:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     strategy:
       matrix:
         platform:

.github/workflows/missing-commits.yml

@@ -10,6 +10,7 @@ on:
 
 jobs:
   up_to_date:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     runs-on: ubuntu-24.04
     steps:
     - uses: actions/checkout@v4

.github/workflows/nix.yml

@@ -39,6 +39,7 @@ concurrency:
 
 jobs:
   dependencies:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     strategy:
       fail-fast: false
       matrix:
@@ -358,6 +359,7 @@ jobs:
   # later
 
   instrumentation-build:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     env:
       CLANG_RELEASE: 16
     strategy:

.github/workflows/windows.yml

@@ -21,6 +21,7 @@ concurrency:
 jobs:
 
   test:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'NoCI') }}
     strategy:
       fail-fast: false
       matrix: