initialize topics-index

Intialize the index with:
- current index
- script to build the index
- github action to weekly check for new optech topics
- updated README

.github/workflows/update-topics.yaml

@@ -0,0 +1,67 @@
+name: Update Topics Index (Weekly)
+
+on:
+  schedule:
+    - cron: '0 0 * * 0'  # Runs at 00:00 UTC every Sunday
+  workflow_dispatch:      # Allows manual triggering
+  push:
+    branches:
+      - 'test/*'         # Runs on any branch under test/
+
+# Add explicit permissions for the GITHUB_TOKEN
+permissions:
+  contents: write  # Allows pushing to the repository
+
+jobs:
+  update-topics:
+    runs-on: ubuntu-latest
+
+    # Add environment variables to control behavior
+    env:
+      IS_TEST: ${{ startsWith(github.ref, 'refs/heads/test/') }}
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.11'
+
+      - name: Install dependencies
+        run: pip install -r scripts/requirements.txt
+
+      - name: Build Index
+        run: python scripts/build_index.py
+
+      - name: Check for changes
+        id: changes
+        run: |
+          git diff --quiet || echo "changes=true" >> $GITHUB_OUTPUT
+
+      - name: Configure Git
+        if: steps.changes.outputs.changes == 'true'
+        run: |
+          git config user.name "GitHub Actions Bot"
+          git config user.email "[email protected]"
+
+      # Add debug information in test mode
+      - name: Debug Info (Test Mode)
+        if: env.IS_TEST == 'true'
+        run: |
+          echo "Changes detected: ${{ steps.changes.outputs.changes }}"
+          git diff --stat
+          git status
+
+      - name: Commit and push if there are changes
+        if: steps.changes.outputs.changes == 'true'
+        run: |
+          git add topics.json TOPICS.md
+          # Add [TEST] prefix to commit message on test branches
+          if [[ "${{ env.IS_TEST }}" == "true" ]]; then
+            git commit -m "[TEST] Auto-update topics index"
+          else
+            git commit -m "Auto-update topics index"
+          fi
+          git push

README.md

@@ -1,2 +1,60 @@
-# topics-index
-A list of Bitcoin topics 
+# Bitcoin Topics Index
+
+An extensive index of Bitcoin-related topics, combining and enhancing the established [Bitcoin Optech Topics](https://bitcoinops.org/en/topics/) with additional relevant entries.
+
+See [TOPICS.md](TOPICS.md) for the categorized index or [topics.json](topics.json) for the machine-readable format.
+
+## Repository Structure
+
+```
+.
+├── topics/             # Bitcoin topics
+│   ├── topic1.yaml
+│   ├── topic2.yaml
+│   └── ...
+├── scripts/           # Build and maintenance scripts
+│   └── build_index.py
+├── topics.json       # Machine-readable index
+├── TOPICS.md         # Generated documentation
+└── README.md
+```
+
+## Topics Format
+
+Each topic is defined in YAML format with the following structure:
+
+```yaml
+title: "Topic Title" # Display name of the topic
+slug: "topic-slug" # URL-friendly identifier
+categories: # List of categories this topic belongs to
+  - "Category 1"
+  - "Category 2"
+aliases: # Optional: Alternative names for the topic
+  - "Alternative Name"
+  - "Another Name"
+excerpt: "A comprehensive description of the topic."
+```
+
+## Usage
+
+### Building the Index
+
+To build the combined index and documentation:
+
+```bash
+python scripts/build_index.py
+```
+
+This will:
+
+1. Fetch the latest topics from Bitcoin Optech's [/topics.json](https://bitcoinops.org/topics.json).
+2. Combine them with additional topics from the `topics/` directory
+3. Automatically generate miscellaneous topics for each category to support uncategorized content
+4. Generate `topics.json` with the complete topics data
+5. Create `TOPICS.md` with categorized listings
+
+### Adding Topics
+
+1. Create a new YAML file in the `topics/` directory
+2. Follow the topics format described above
+3. Run the build script to update the index