chore(ci): remove custom detect-changes action and replace with tj-actions/changed-files

Remove the custom GitHub Action for detecting file changes and replace it
with the widely-used `tj-actions/changed-files` action. This change
simplifies the maintenance of the CI configuration by leveraging a
well-supported third-party action. It also ensures more reliable and
up-to-date functionality for detecting file changes, which is crucial
for optimizing CI workflows by skipping unnecessary jobs.

Author: kzndotsh

.github/actions/detect-changes/action.yml

@@ -72,11 +72,18 @@ jobs:
       contents: read          # Required for checkout
       pull-requests: write   # Required for Pyright annotations
     steps:
-      # SMART CHANGE DETECTION WITH CHECKOUT
+      # REPOSITORY CHECKOUT
+      # Full history needed for accurate change detection
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      # SMART CHANGE DETECTION
       # Detects Python file changes to skip unnecessary runs
       # Includes Python source, config files, and dependencies
       - name: Detect Python changes
-        uses: ./.github/actions/detect-changes
+        uses: tj-actions/changed-files@v45.0.8
         id: python_changes
         with:
           files: |
@@ -130,11 +137,16 @@ jobs:
     permissions:
       contents: read
     steps:
-      # SMART CHANGE DETECTION WITH CHECKOUT
+      # REPOSITORY CHECKOUT
+      # Shallow clone sufficient for linting current state
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      # SMART CHANGE DETECTION
       # Only runs when documentation files change
       # Improves CI performance for code-only changes
       - name: Detect Markdown changes
-        uses: ./.github/actions/detect-changes
+        uses: tj-actions/changed-files@v45.0.8
         id: markdown_changes
         with:
           files: '**/*.md'
@@ -204,11 +216,16 @@ jobs:
           - type: Shell Scripts
             files: '**/*.sh,**/*.bash,scripts/**'
     steps:
-      # SMART CHANGE DETECTION WITH CHECKOUT
+      # REPOSITORY CHECKOUT
+      # Shallow clone sufficient for infrastructure validation
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      # SMART CHANGE DETECTION
       # Each matrix job only runs if relevant files changed
       # Improves efficiency by skipping unchanged categories
       - name: Detect ${{ matrix.type }} changes
-        uses: ./.github/actions/detect-changes
+        uses: tj-actions/changed-files@v45.0.8
         id: infra_changes
         with:
           files: ${{ matrix.files }}

.github/workflows/ci.yml

@@ -85,11 +85,16 @@ jobs:
           - '3.12'
           - '3.13'
     steps:
-      # SMART CHANGE DETECTION WITH CHECKOUT
+      # REPOSITORY CHECKOUT
+      # Complete repository needed for comprehensive test execution
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      # SMART CHANGE DETECTION
       # Analyzes changes to determine if test execution is necessary
       # Includes all test-relevant files: source code, config, and tests
       - name: Detect Python changes
-        uses: ./.github/actions/detect-changes
+        uses: tj-actions/changed-files@v45.0.8
         id: python_changes
         with:
           files: |