Add log ingestion tool for loading signature logs into SQLite

- Parse signature messages from log files extracting app info, device
  details, and feature flags (autofill, touchID, offline login, etc.)
- Support both plain .log and gzip compressed .log.gz files
- File discovery by date range (YYYY/mm/dd directory structure)
- Batch inserts for performance with large files (10GB+ per day)
- Index on session_id and version for efficient queries
- Extensible parser architecture via MessageParser trait

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.github/workflows/dependabot-auto-merge.yaml

@@ -0,0 +1,34 @@
+name: Dependabot Auto-merge
+
+on:
+  pull_request:
+    types:
+      - opened
+      - synchronize
+      - reopened
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  dependabot-automation:
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' }}
+    timeout-minutes: 13
+    steps:
+      - name: Dependabot metadata
+        id: metadata
+        uses: dependabot/fetch-metadata@21025c705c08248db411dc16f3619e6b5f9ea21a # v2.5.0
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+      - name: Approve & enable auto-merge for Dependabot PR
+        if: |
+          steps.metadata.outputs.update-type == 'version-update:semver-patch' ||
+          steps.metadata.outputs.update-type == 'version-update:semver-minor'
+        run: |
+          gh pr merge --auto -s "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          PR_TITLE: ${{ github.event.pull_request.title }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}